A church of bones, decorated with 40,000 human skeletons.

Modern art commemorates one of the first military actions of World War II.

A huge wooden clock that is so beautiful its creator was forcibly blinded.

The walls and ceiling of this Polish church are decorated with thousands of skulls, with another 21,000 skeletons just below.

An underground city of salt.

Real bones which are said to have belonged to a Polish dragon.

The silly symbol for an underground protest group is now scattered around the city.

Relive a Polish uprising via an enormous, century-old cyclorama.

Ant sculptures march up the side of what used to be an iconic spot in punk rock lore.

Dr Barnes' $25 billion private collection of art and arboretum.

Golden and naked, the figure that was once the highest point in New York is all that remains of the second Madison Square Garden.