The Underground Argyll Arcade: Glasgow’s Most Persistent Urban Legend

Every city has its underground legend. Rome has its catacombs. Edinburgh has Mary King’s Close. Glasgow has several, because Glasgow is a city built on top of itself in layers that the Victorian expansion, the railway construction, and the relentless westward march of nineteenth century development left buried rather than demolished, and the rumours of what lies beneath the streets have never entirely gone away.

The most specific and the most stubbornly persistent of these Glasgow underground legends concerns the Argyll Arcade, Scotland’s oldest shopping arcade, an L-shaped covered walkway that has been connecting Argyle Street to Buchanan Street since 1827. The legend, passed from Glaswegian to Glaswegian across an indeterminate number of decades, in pubs and on forums and in the particular way that city mythology circulates, goes like this:

There is an exact replica of the Argyll Arcade directly beneath the existing one. Whether the underground version is the original and the one above the replica, or the other way around, varies depending on who is telling it. What stays constant is the underground arcade itself, fully formed, lit by the small glass portholes in the floor of the arcade above, preserving beneath the city a Victorian jewellery quarter that the surface world has never quite explained.

Nobody knows where this legend came from. Nobody has definitively proved or disproved it. And it shows no signs of going away.

The Arcade That Started the Rumour

To understand why this particular legend attached itself to the Argyll Arcade specifically, it helps to understand what the building actually is and why it is genuinely unusual.

The arcade was built in 1827 to a design by John Baird Senior, commissioned by a man named John Reid Robertson who contributed his own family home on Buchanan Street to the development project. The result was Scotland’s first covered shopping arcade, an L-shaped passage of ironwork and glass inspired by the grand arcades of Paris and London that cut through the old tenements between Argyle Street and Buchanan Street, connecting two of the city’s main commercial streets under a single glazed roof.

The effect when you walk into it is immediate and still works nearly two centuries later. The light changes. The noise of the street drops away. The pace of movement slows slightly, as it has always slowed in covered shopping spaces where the weather cannot follow you in. The proportions are narrow enough to feel intimate without being cramped, and the glass roof above, which has been overhead in essentially the same form since the 1820s, filters the Scottish light into something softer than the streets outside produce.

It has been associated with jewellers almost from the beginning, and today it is effectively Glasgow’s jewellery quarter, lined with watch shops and engagement ring retailers and the kind of discreetly expensive establishments that have made the Argyll Arcade one of the city’s enduring commercial institutions. Generations of Glaswegians remember pressing their faces against the shop windows while their mothers browsed, waiting for the rain outside to stop. The arcade has always been a place people go to be inside, and inside has always been its great practical virtue.

At the floor of the arcade, if you look down as you walk through, you will notice something that most shoppers have probably never consciously registered: small glass portholes set into the pavement at intervals. These are real. They have always been there.

What they are illuminating below is the question that started the legend.

The Porthole Problem

The glass portholes in the floor of the Argyll Arcade are a documented architectural feature of the building, and they are genuinely unusual. Portholes in a floor imply a space beneath that space, a void that benefits from or requires light from above, and in the context of an arcade that already feels like it belongs to a slightly different world from the streets surrounding it, the portholes have always invited speculation about what they are looking down into.

The most prosaic explanation, advanced by those familiar with the building’s actual history, is that the space beneath the arcade floor was used as a workshop by the jewellers above, a practical extension of their retail premises into the available underground space that the arcade’s construction had created. Several participants in discussions about the legend on the Hidden Glasgow community forum, a website dedicated to Glasgow’s architectural and social history, have suggested this explanation with varying degrees of confidence, noting that the shape and placement of the portholes is consistent with providing light to a working space rather than to a pedestrian level.

This explanation, even if correct, raises an interesting subsequent question: if there is definitely something beneath the arcade floor, and if that something was accessed and used for extended periods, what exactly does it look like down there now? The jeweller’s workshop theory does not require an exact replica of the arcade above. But it also does not rule out the possibility that the space below, built at the same time as the space above, shares something of the same structural character.

The portholes are real. Something is below them. Beyond these two facts, the legend and the available evidence converge on the same territory of genuine uncertainty.

What the Legend Actually Claims

The specific claims attached to the underground arcade legend have varied considerably across the years and the various contexts in which it has been told, and this variation is itself informative about how the legend functions.

In some versions, the underground arcade is a perfect mirror of the one above, with matching shopfronts and the same L-shaped layout, preserved in a kind of suspended animation beneath the Victorian street. In others it is not a replica so much as a predecessor, the original arcade from which the above-ground one was built, left intact when the surface was rebuilt or raised and the new arcade constructed above it. In still others it is neither replica nor predecessor but a separate development, a forgotten Victorian scheme that was built in parallel with the existing arcade for reasons that have not been adequately preserved in any record anyone has found.

The explanations attached to its supposed origins are equally various. Odd council schemes. Forgotten Victorian city planning. A project that was begun and then abandoned when the costs or the engineering or the political will ran out. A space that has always been there and whose purpose was always storage or utility rather than retail, but which has been mythologised into something more dramatic by the city’s appetite for its own underground history.

On the Hidden Glasgow forums, where the legend has been discussed in the specific, architecture-focused way that that community discusses Glasgow’s history, one contributor noted the broader phenomenon with appropriate scepticism: I think all the stories of intact streets below the cobbles of central Glasgow are urban myths. Another described the portholes directly, noting that they run from the Buchanan Street entrance to just before one of the internal units, and suggesting that whatever is below them was used for the jewellers’ workshops. The forum discussion, like the legend itself, reached no firm conclusion.

Glasgow Underground: A City Built on Itself

The Argyll Arcade legend does not stand alone. It exists within a broader tradition of Glasgow underground mythology that is rooted in genuine architectural fact rather than pure invention, and understanding this context helps explain both why the legend exists and why it refuses to go away.

Glasgow’s Victorian expansion was rapid enough and ambitious enough that buildings, streets, and entire districts were regularly built over rather than built around. The area beneath Glasgow Central Station preserves elements of Grahamston, a district that was effectively demolished and built over to create the station, and the spaces beneath the station’s famous umbrella structure are among the better-documented examples of Glasgow’s buried past. The Argyle Line railway, the cut-and-cover tunnel that runs beneath Argyle Street itself, passes directly beneath the street above the arcade, adding another layer to what lies underground in that specific part of the city centre.

The geological and hydrological history of central Glasgow adds a further dimension. The area around Argyle Street was historically prone to flooding from the Clyde before the river’s banks were properly contained, and the raising of street levels to manage this flooding is one of the explanations offered in various discussions for why certain basements and underground spaces in the area are deeper and more extensive than modern visitors might expect. A street that floods regularly is a street whose buildings tend to build upward rather than simply sideways, and the accumulated result of that tendency over two centuries is a cityscape with more underground than it shows above ground.

In this context, the Argyll Arcade legend is not simply an isolated piece of wishful thinking. It is one expression of a genuine and broader truth about Glasgow, which is that the city has always had more below it than it shows on the surface, and that the relationship between the visible and the buried is a live and ongoing question rather than a settled historical fact.

Why This Legend Persists

Urban legends about hidden underground spaces persist for specific reasons, and the Argyll Arcade legend demonstrates most of them with unusual clarity.

There is the physical evidence. The portholes are real and undeniable, and a porthole in a floor is an invitation to imagine what lies below it. The legend does not require anyone to invent the premise from scratch. The premise is already there, in the floor, for anyone who looks down while walking through the arcade.

There is the building’s own strangeness. The Argyll Arcade is genuinely unlike anything immediately around it, a Victorian interior that has barely changed in two centuries, sitting in a city centre that has been substantially rebuilt at least twice in that period. The sense that the arcade belongs to a different time from the streets it connects is not an illusion. It genuinely does, and the feeling that it might extend into other times, other spaces, other versions of itself underground, follows naturally from that.

There is the broader Glasgow appetite for its own hidden history. The city has always been interested in what lies beneath it, and the community forums and local history groups that discuss these questions with genuine seriousness provide a continuous social infrastructure through which legends like this one circulate and are kept alive.

And there is the simple pleasure of the idea. An underground arcade, a mirror image of the jewellery quarter above, preserved beneath the city in the specific quality of light that the portholes provide, is a genuinely compelling image. It is the kind of thing that once suggested refuses to fully leave the imagination, and the imagination of a city is a collective thing that persists long after any individual has forgotten where the idea originally came from.

What Is Actually Down There

The honest answer, which the legend has always implicitly acknowledged by never producing a witness who claims to have been into the underground arcade, is that nobody outside the building’s management and possibly not even they can say with complete confidence what the space beneath the Argyll Arcade floor actually contains now.

The jeweller’s workshop explanation is the most structurally plausible. The portholes are consistent with it. The layout suggested by those who have noted the portholes’ distribution, running from the Buchanan Street end through much of the main run of the arcade, is consistent with a space that was functional and used rather than simply void.

But the space has been beneath the arcade for nearly two hundred years, and things accumulate in spaces over two hundred years. What was a jeweller’s workshop in the Victorian period, actively lit by those portholes, may have become something less deliberately maintained over the course of the twentieth century. Spaces that begin as functional tend to end as storage, and storage tends to end as accumulation, and accumulation in Victorian buildings has a way of becoming archaeology faster than anyone expects.

Whatever is down there, the portholes still look into it. The light from the arcade above still falls through them. And the legend of what lies beneath the oldest shopping arcade in Scotland keeps circulating through the city, told in pubs and on forums and by the particular kind of Glasgow person who knows the place well enough to look down at the floor when everyone else is looking at the jewellery.

Look down at the portholes next time you walk through. Consider what they are looking into.

Nobody has produced a final answer. The city is still working on it.

If you want to read more tales about Glasgow’s legends and folklore, click here.