Rome's semi-secret peephole vista is also a former Crusader stronghold.

Hundreds of lucky felines haunt the ruins where Caesar was murdered.

Ancient ruins hidden underneath a modern luxury hotel.

Ever hear of the Milazzo Cage?

A modern sliver of architecture in Roma.

The only "Egyptian" pyramid in Europe and the legendary tomb of Remus.

The signs of a long buried road can still be found hidden beneath a London sewer grate.

On a wall in linear London, a plaque hangs at the high water mark of one of the worst floods in fictional Kcymaerxthaereal times.

Hidden beneath the streets of London is a secret subway that only carried mail.

The perfectly preserved underground rooms where Churchill plotted the war against Germany.

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

An easily overlooked stretch of ornate window fronts and gaslight lamps that could be right from the pages of Dickens.

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