The only remaining arch of the oldest stone bridge in Rome stands in the middle of the Tiber.

A detailed pachyderm supports Rome's smallest Egyptian obelisk.

The final resting place of the poets Shelley and Keats.

The skull of the patron saint of lovers lies in the Basilica di Santa Maria in Cosmedin—maybe.

Architectural monsters are devouring this palace's every door and window.

The engineering wonder and pleasure dome of a much-maligned emperor still holds undiscovered secrets.

This fairy-tale castle would make Dracula (who is said to have been imprisoned there) jealous.

The fairy tale castle of the "fairy-tale king."

An avant-garde artist is survived by his seaside garden.

A house of bones — but nobody is quite sure to whom they belong.

This stately estate house features a tower covered in a bright, modern mural.

Now famous as the "Harry Potter bridge," this impressive concrete viaduct has long been an icon in its own right.

Soak up some local history in this restored Edwardian era swimming pool.

Locals call it the "Give Peas a Chance" bridge because of its distinct graffiti.

A kaleidoscopic warehouse-maze of handmade neon signs.

One of the few remaining casualties of the London Blitz, this destroyed church has become an enchanting public garden.

An unsanctioned shrine that sprung up outside the late singer's home is causing a stir in London's Highgate neighborhood.

This hidden green space is the city's second largest conservatory.

A quiet memorial to those who died saving others in the heart of the City of London.

The fences outside some of South London's estates are made from recycled World War II stretchers.

This museum tucked below a charming cafe gives a brief snapshot of photographic history.

Several plaster noses are hidden in plain sight around London's Soho neighborhood.

Giant, friendly pelicans in Central London, the most unlikely of places.

A traditional American farmhouse plopped in the middle of a Piccadilly courtyard.