London is full of monumental statues, but its tiniest piece of public art is barely a couple of inches tall and hides in plain sight in the heart of the City. On Philpot Lane, a narrow street just off Eastcheap near Monument, two tiny mice can be spotted gnawing on a wedge of cheese, perched high on the corner of a building facade. Most walkers pass directly beneath without ever noticing.

The miniature carving has become one of the capital's favourite oddities precisely because it rewards anyone willing to slow down and look up. There is no plaque explaining it, no official artist credited, and the City of London has never given it a formal listing — it simply sits there, a small mystery on an otherwise unremarkable office-fronted street.

Local legend attaches a darker story to the mice. One version ties the sculpture to a 19th-century construction accident on the site, in which two workmen reportedly quarrelled over missing sandwiches — blame was placed on a colleague, a fight broke out and one man fell to his death. The supposed punchline: the real culprits were mice stealing the food. It's a great story, though historians treat it as folklore rather than fact, and there's no firm record backing it. What is more plausible is that the carving is simply a piece of Victorian whimsy, added by craftsmen when the buildings along Philpot Lane were rebuilt after the area's redevelopment in the mid-1800s.

Finding it is the fun part. Philpot Lane runs between Eastcheap and Fenchurch Street, a short stroll from the Monument to the Great Fire of London and a few minutes from Bank station. The mice sit high on the corner of a building, so keep your eyes raised as you walk — and be patient, as pedestrians often cluster on the narrow pavement once they've spotted it.

Why bother with a carving you could blink and miss? Because this is London at its best: a city where a five-minute detour between bigger sights turns into a scavenger hunt. It pairs neatly with other nearby curiosities — the giant brass cats and other animals hidden on the Homeward Bound sculpture along Eastcheap, Giro the Nazi dog's grave in St Mary's churchyard (an odd but real piece of local lore), or the通风 shafts and survivors of the Great Fire around Monument itself. If you enjoy a self-guided wander, you can build a whole hour of micro-sightseeing around this one small corner of the City without spending a penny.

The mice also make a good starter for anyone trying the increasingly popular hobby of hunting hidden London details: mini carvings, ghost signs, Roman walls poking out between office towers. Once you start noticing them, the City stops feeling like a sterile financial district and starts feeling like a layered, centuries-old puzzle.

The mice of Philpot Lane won't take up much of your itinerary — that's rather the point. Add them to a walking route through the Square Mile and you'll come away with one of London's least-known stories, all two inches of it.