Peer through the Barrier. What do you see? Things absent for nearly all time, yet for this instant they bend the landscape around them as though they be most important.

Between the Thames Barrier and the English capital, three peninsulas form a buffer zone that slows the onslaught of the tides. These reaches were always beyond the limits of London proper, a waterlogged hinterland that much like the marshes downstream were thought of as belonging to the rural provinces of Essex (north) and Surrey (south), not the City.

Slowly the attentions of kings, sailors and merchants followed the River out this way. Then England transformed into an industrial empire of global reach and ambition. In the process, so did these margins metamorphose utterly and beyond recognition, for it was here that much of the actual work of those projects was done. But as industry and empire alike have stumbled, stuttered and sank into history, these banks have transformed yet again. Still now they transform. Perhaps no stretch of the Thames has experienced so much flux, nor seen the very landscapes that frame its meanders so tied up in the meanders of the English national story.

Some of those stories propelled these riverbanks to international significance. The name of Greenwich is known in all countries of the world because of things done there in centuries past; some of their people might even pronounce it the way the English do (“Grenich”). Meanwhile much of what the British Empire looted off them passed through the renowned docklands that dominated both banks of the river here. Today these shores are still changing, and hurl new names round the world like Canary Wharf. But is this a flowing onwards, or rather a drastic bend in history much like the river’s own sudden hairpin around the Isle of Dogs? Are the English building their modernity ever higher here? Or has that modernity subsided, to soak into the marsh and wash away on the Thames’s tides, replaced where it once stood with something, if not darker (for the shadows of the docks were dark indeed), then altogether hollow?

Let’s find out.

Start:Thames Barrier (nearest station: Charlton)

End:Tower Bridge (nearest station: Tower Hill)

Length: 14.5km (9 miles)

Region: Greater London – Royal Borough of Greenwich, Borough of Lewisham, Borough of Southwark

Topics: Greenwich Peninsula, the Millennium Dome, the Docklands, the Greenwich meridian and GMT, Surrey Docks, Tower Bridge

Through a tunnel – and of course there is a tunnel – we leave the Barrier and step onto the Greenwich Peninsula.

Now the London Monster is right there in its nest. It inhabits the central and largest peninsula, but first let’s consider the current one.

The Greenwich Peninsula is another lump of marshland which once bore the same name as the stretch of river down its eastern flank: Bugsby. Whether Bugsby was a person or otherwise is lost to history and has attracted numerous theories. The possibility that it derives from bugbear, bogey (as in bogeyman) or suchlike might be more plausible, because these are bloodied, haunted swamps.

Remote enough to host pirates till the late nineteenth century, Bugsby’s Marshes were where the irate London river authorities installed their most English of countermeasures. After putting suspected pirates to death at Execution Dock in Wapping, they would hang their decaying corpses in chains or cages over the river in a practice called gibbetting. This was supposedly to deter others, but seems to have had about as much effect as any authoritarian power trip that ignores structural causes.

The docks and factories came relatively late to the Greenwich Peninsula. From the late nineteenth century it caught the overspill of sectors like iron and steel, shipbuilding, chemicals, and most importantly the great big gasworks of the South Metropolitan Gas Company. All these have long since vanished, but as downriver, their ruined wharves and jetties still stand, a few repurposed by the residual industries that linger along these flanks.

All of a sudden, it is as though the path leaves one timeline and enters another.

The name of this bizarre residential complex is the Millennium Village, constructed – yes – in the new millennium on the site of the old gasworks. If you believe the people who put it there, it features state-of-the-art architectural design, sustainable energy usage and waste disposal, and integrated shopping and community spaces. Just don’t tell the people who’ve moved in that there are skeletal pirates and gibbetted zombies underneath (though the moment they surfaced they would probably get segregated into a separate playground for being in a lower income band anyway).

All along these riverbanks the soundtrack is the clanging and hammering of the construction symphony orchestra. These developments are spin-offs from the regeneration of the fallen docklands and industrial remnants of the lower Thames, a free-market frenzy unleashed under the Thatcher government in the 1980s that has ushered in the full-scale transformation of this landscape up to and including the skyscrapers on the Isle of Dogs ahead. The character of the new developments and the impacts on the working-class communities that populated this area through the industrial age have been extremely controversial, and are a prism of this country’s values in the long shadow of its market fundamentalist revolution.

Greenwich Millennium Village: housing, housing everywhere, and still the worst homelessness crisis in living memory.

On the north bank the regeneration brigade is moving in on Silvertown, once named for the S.W. Silver and Co. rubber works around which it grew up.

Artworks unfamiliar to these marshes, such as this good-morning mermaid and tentacle hentai, have been placed at strategic intervals along the riverbank.

And then of course there’s this bloody thing.

In the year of the millennium, more eyes likely fell on this peninsula than all those in its prior history put together. They did not linger long. That is because this was the chosen site for a certain Prime Minister Tony Blair, then at the height of his popularity and yet to join George W. Bush’s United States in the destruction of Iraq, to install what he insisted would be ‘a triumph of confidence over cynicism, boldness over blandness, excellence over mediocrity’. Instead the Millennium Dome was a multimillion-pound shambles of public disillusionment and gross financial ineptitude. Any greater meaning to this ‘monstrous blancmange’, as Prince Charles dubbed it, was lost in a quagmire of expensive and vacuous nothing. They eventually managed to sell it off, and it is now an ordinary entertainment space named the O2 Arena after its sponsoring telecoms company.

The Great White Elephant in person.

You can pay to clamber around on it.

Opposite the Dome are the much-transformed quays of Blackwall, best known for the Blackwall Tunnel which funnels road traffic under the river here.

The Docklands Light Railway (DLR). One of the newest additions to the London Underground family, it was opened in 1987 to ferry the new class of corporate samurai around their conquests in the converted docklands.

Peer through the blurry maze of cranes and you can just make out the brick warehouse with a lighthouse attached. This is Bow Creek Lighthouse, which though now an ‘art space’ still marks the arrival of the river Lea, one of the Thames’s most important tributaries with a long history featuring canalisation, water works and Viking raiders.

The west side of the Greenwich Peninsula is an ordeal to walk through because the ongoing battle between lingering industries and hungry redevelopers, most conspicuously on the old Morden Wharf, has overwhelmed the riverside, path and all. A cumbersome and poorly-signposted detour is forced down the angry dual carriageway that feeds the Blackwall Tunnel.

Terraced walls round the river bend. The tide is low, so you can see they’ve built three layers to allow different ecosystems to develop based on exposure to different tide levels. Almost all the Thames’s banks in London are built up and most are vertical walls. It seems they have started to realise that this is not good for the river ecology and are exploring ways to fix it.

Here and there, even right on top of the present-day infrastructure, there is evidence that a different world once stood here.

That lonely gas holder is all that remains of the former gasworks. Behold the Greenwich Peninsula: yesterday and yesterday-pretending-to-be-tomorrow side by side.

Here one comes face-to-face with the largest peninsula. Its skyscrapers leer down with unbridled menace, but at this close range there are cracks in their world in plain sight. The heritage they smashed up to build their nest is more complicated than it looks, and ropes together some of the most revealing problems in the story of the English nation.

At the base of the financial district is a smattering of leftover cranes and industrial buildings. Notice here the waterway that cuts into the Isle of Dogs, helpfully labelled ‘West India Dock’. In there the plot thickens.

This, too, was a marshland outside London with a name whose origins are lost in obscurity. Up till around 1800 you could tell this city’s entire story without mentioning the Isle of Dogs once. Then it became the place where England happened.

By virtue of the Thames, London had always been a trading city. But when the tides of industry swelled and the talons of empire stretched, all the numbers involved erupted. Population, activities, food, coal, timber, goods to export and exotic materials to import – the river bore the burden of this as it clogged with ships from bank to bank. The Pool of London, the stretch of river adjoining the city centre, became the fabled ‘sea of masts’. Cargoes took forever to berth and rotted away on ships or quaysides if thieves (or rather, desperate people displaced by Enclosureinto urban poverty) didn’t get to it first.

The English police, too, were born in the river. The Marine Police Force emerged in 1798 precisely to guard these masses of cargo. It spread onto the land and was later developed by Home Secretary Robert Peel into the Metropolitan Police.

The politicians and merchants got together and decided on a solution: docks. Serious docks – look again at the map and you can easily see the iconic blue rectangles they carved into the land. Endorsed by the government (and hated by the traditional lightermen and watermen whose control of river trade they broke), the huge trading companies that had emerged triumphant out of the English age of piracy scrambled to build their own dock networks, each one a veritable fortress behind whose state-of-the-art security its corporate masters guarded a jealous monopoly on handling their designated range of goods.

So were the docklands born, right there on the Isle of Dogs where the skyscrapers are now. In charge of those first docks, built in 1802, was the association of companies that dealt in Caribbean sugar and rum – that is to say, the Atlantic slave traders. The West India Docks (as in West Indies, not actual West India) would be where they made their killing out of one of the worst crimes against humanity to ever take place on this Earth. In the years and decades ahead, other companies followed suit – the infamous East India Company with its East India Docks; unaffiliated City merchants with the London Dock; and a tussle of mainly timber merchants with the Surrey Docks on the third peninsula, Rotherhithe. Eventually a bunch of railway entrepreneurs went further east onto the Plaistow Marshes and dug out the most ambitious docks of all, the Royal Docks trio (Royal Victoria, Royal Albert, and King George V); a still vaster set, much further east at Tilbury, was not successful but would get its revenge a century later.

Into these docks poured immeasurable mountains of colonial plunder. You decide if this amounted to something new, or made this stretch of the Thames merely the biggest, most glorified pirates’ den in the world.

The work, however, was real. Huge numbers of displaced rural people and foreign immigrants found work in the docks and their asteroid belt of industries, and many of east London’s working-class neighbourhoods grew up around them. These dock communities and cultures would play an enormous role in the rise of the English labour movement, its struggle for better working conditions, and later the ferocious conflict with the free-market revolutionaries who rained these glass missiles down upon their world.

This world of the docks lasted around a century and a half. It experienced much turbulence – their nationalisation under the Port of London Authority (PLA – if you know the Thames in London you will have seen their vessels) when the dock companies’ squabbles threatened to bring it all crashing down; and in particular two world wars, the second of which saw them specially targeted by the Nazi Luftwaffe and reduced to a hellscape of death and flames. They survived that, indeed recovered, but could not survive the out-competing of Britain by the new industrial powers; nor the loss of colonies which declared independence and refused to be plundered anymore; nor the new cargo technology, in particular gargantuan container transport, which demanded port facilities on an entire new order of magnitude. One by one the docks closed down, leaving swathes of riverside working-class communities marooned in dereliction and poverty.

Along came Michael Heseltine and his brainchild the London Docklands Development Corporation (LDDC), which was given sweeping powers (over the fuming heads of the Labour Party-controlled borough councils) to buy up and redevelop these territories as they saw fit. Private developers were lured onto the Isle of Dogs with promises of a free-market paradise of tax concessions and deregulation, just as Thatcher cut loose the shackles on the financial sector. Down slammed the skyscrapers, impaling the old slums and reducing the dock basins to mere water features for these glistening phalluses, erect at the very thought of a future of infinite capital. Sucking up the resources of the nation they stand in, they have proven the true successors to the West India slavers and pirates who once ran things here. They have even inherited the name of one of their berths: Canary Wharf.

Canary Wharf. So named for the Canary Islands, from where the West Indies slavers shipped in fruit, and whose people were the victims of the first European colonial genocide. Piracy by the cutlass and cannon was now piracy by the computer. Like the dock companies, the financial swashbucklers promised, from high in their cockpits over this haunted marsh, that the proceeds would trickle down. As with the docks, they didn’t. Instead this celebrated rebirth of a new modernity for England collapsed into the 2007-8 financial crisis, bringing the public legitimacy of this country’s entire political and economic order crumbling down with it. This story is still playing out in the Brexit crisis.

Hence the significance of the story of the docklands. It is the story of the rise, fall, and staggering undeath of English modernity itself.

The Isle of Dogs seen from the east. Contrast the north (right) with the south (left).

If you want a closer look at this story then I strongly recommend the Museum of London Docklands, which has managed to capture one of the former warehouses on the West India quay. But now take a deep breath, because after all that, everything changes again.

The Greenwich Reach.

The paving ends, the cobbles begin, and once again the river flows out of one world and into another.

Even amidst these churning swamps of time, Greenwich stands proud. Chances are you already know its name.

Nestled at the bottom of the Thames’s loop, the ‘green trading settlement’ has a long history. Perhaps its attractive situation – a hill, and views both up and down the river - drew the royal outpost that was present here from at least the Plantagenet period and eventually grew into the Palace of Placentia (likely from Latin placēre, 'to please').

The Old Royal Naval College. The site of this grand edifice anchors the stories of Greenwich and has experienced several incarnations, the Palace of Placentia being the first of national consequence.

The palace peaked in popularity under the Tudor dynasty, and it was here that their great reformer and terror Henry VIII was born in 1491. But after the Restoration (the return to monarchy in 1660 after the civil war) it was pulled down. English modernity may have fallen in the docklands but it was in this earlier period that some of its most important foundations were set down, and Greenwich became the drawing board for a set of ambitious new projects under Charles II, the restored Stuart king. By the 1690s the current complex of buildings had arisen, designed by architects including the renowned Christopher Wren to serve as the Royal Hospital for retired sailors of the newly-emerged Royal Navy. That ran all the way till 1869, when it decanted its elderly sailors and switched to training young ones instead as the Royal Naval College. In that capacity it made it all the way to 1998, when the shrinking navy left Greenwich for good.

The main part of the complex is now under lease to the University of Greenwich, hence the graduation celebrations glimpsed here.

Greenwich’s international fame however comes from the Royal Observatory, which perches on the hillside above the river. This was one of Charles II’s projects in the 1660s and 70s, its site carefully chosen as the lair for the newly-appointed Astronomer Royal to study the stars with what for the English was a new and meticulous scientific rigour. The idea was to use that research to improve navigation for British ships, but with its contributions to the discovery of how to calculate longitude (east-west position) at sea, the Greenwich observatory ended up as the point through which the British prime meridian(the zero-degree longitude line by which all others are measured) was chosen to run. In 1884 it was agreed at an international conference that this Greenwich meridian would be established as the global standard.

That wasn’t all. The research that eventually solved the longitude problem concerned its calculation using the time difference between a ship’s location and a fixed reference point (i.e. chronometry). The time at Greenwich became that fixed reference point for British seafarers to set their clocks to. By the late nineteenth century this Greenwich Mean Time (GMT) had been set as the unified time across all of the British Isles, a practice previously unnecessary but now required by railway timetables. Given the British Empire’s political clout, both GMT and the prime meridian went on to become common standards in maps and clocks around the world.

The Royal Observatory spotted from the riverside. The red sphere is called the Time Ball, installed in 1833 to help mariners on the river calibrate their ships’ clocks to GMT. To this day it drops down the pole at exactly 1pm every day.

Fun fact: unlike latitude, east-west longitude measurement is completely arbitrary. There is no scientific basis to setting longitude lines in one position or another; you can put them wherever you want. The decision to take the Greenwich meridian as standard was entirely political. Just ask the French. As long-term rivals of the English they were aghast at the 1884 decision to set the prime meridian in London and refused to accept it, stubbornly continuing to use one that ran through Paris for another three decades.

The Observatory now houses an excellent museum where you can find out more about all this. Along with the riverside museums it ensures that Greenwich is usually packed with tourists, so go when it is pouring with rain if you don’t like crowds.

Another of Greenwich’s front-line landmarks is the Cutty Sark, which in the late nineteenth century shipped Chinese tea and Australian wool to England at record-breaking speeds. It now sits here atop its own museum, so Chinese tourists can pay to go inside and wander around the tea crates it grabbed off their country after ruining it with opium.

Which all goes to show that if you want to bring people in, it helps to have some real history.

Up the west side of the Isle of Dogs, the third marshy peninsula, Rotherhithe, forms the final headland before the City of London proper. It is reached from Greenwich through what was once the fishing village of Deptford, converted by Henry VIII into a naval yard. Another settlement further up grew around the abbey of Bermondsey, which like most English monasteries was wrecked by – guess who – Henry VIII. It’s funny, and not in a pleasant way, how that individual manages to barge into so many stories in this country and smash everything up.

The river-facing residences of Deptford overlook the Limehouse Reach.

This statue of the Russian tsar Peter I (‘the Great’, 1672-1725) looks out on the river from a modern apartment complex in Deptford. During semi-incognito travels around Europe in 1697-8 he stayed in Deptford and studied shipbuilding techniques he would later apply in his creation of St. Petersburg. The English relationship with Russia has always been complicated. Though displays of hostility seem the default setting, they owe each other a lot.

These now feel like sleepy residential neighbourhoods, if less opulent than the brazen likes of the Millennium Village. Formerly however they were the lair of the Surrey Commercial Docks, which specialised in Scandinavian and Baltic timber as well as Canadian grain. The Surrey Docks were always the oddity in the dock family, set apart from the others by their specialist work culture. This work came to an end in the 1970s and 80s just as at the other docks, but in spite of the area’s redevelopment it stands out for the sheer quantity of old stories crammed into every corner of its landscape. Every rusting wharf, warehouse, pub, set of stairs, or mere piece of lock or quay machinery memorialises something of its own; as though this peninsula’s future vision, humbler than that of Canary Wharf, is built around and in some cases into the fossilised remnants of its old world.