This beautiful Victorian ironwork masterpiece was built to keep London from smelling like poop.

The biggest and deepest Cold War bunker open to the public can be found in southeast England.

One of the largest sculpture collections in the U.K. features history's greats, from Bob Dylan to Galileo, in bronze.

Abstract dinosaur models in London.

This foolish Victorian sea fort was converted to a deluxe hotel.

The remains of Crystal Palace Great Exhibition of 1851.

A 200-year-old prison that now houses a peculiar crime museum.

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

Below a historic English market town lies a secret underground city complete with kitchens, laundries, storerooms, and an underground lake.

Northern Ireland's Brobdingnagian stepping stones.

The hidden "ballroom" under a mansion lake was built by a criminal who ate a cyanide pill during his trial.

This astonishingly geometric cave has inspired everyone from Jules Verne to Pink Floyd.

The Origin of On the Origin of Species.

Underground hospital complex constructed by slave laborers during the German occupation of the Channel Islands.