Instruments, apparatus, and rare books all relating to chemistry and its related sciences.

Mural made of 100,000 pieces of hand blown glass, and until recently, the largest glass mural in the US.

A clone-tree in Washington Square Park sprung from seeds that went to the Moon and back.

A layered tribute to the work of mosaicist Isaiah Zagar.

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

This little-known collection holds everything from "Dracula" notes, to the manuscript of "Ulysses," to the forged works of Shakespeare.

A daily replay of the experiment that proved the rotation of the Earth.

A tour de force of a fountain, memorializing a man who loved fountains more than anything else.

This beloved marketplace mascot poops money and grants good luck.

The sounds of the world's largest fully functioning pipe organ dazzle shoppers at a Philadelphia Macy's.

The first American department store, and home to the largest operating musical instrument in the world.

This elaborate towering structure was once famed for its revolutionary height.

Once the tallest building in the world, this abandoned church is now a monument to the destruction of WWII.

The medieval institution is home to the precious treasure stolen in World War II in one of the greatest art thefts of the 20th century.

Ruins of a German Castle on top of a towering stone pillar.

The bridge that cost Germany a World Heritage Site.

When the rain falls, this drain system turns into a musical instrument.

In addition to fine dairy products, the world's most beautiful milk shop also offers a feast for the eyes.

Tourists often confuse this beautifully ornate former cigarette factory for a mosque.

A famous big wave from Japan serves as a tribute to the victims of the disastrous Elbe flood.

This Dresden church was purposely rebuilt Protestant after being demolished in World War II.

Residents of Berlin take their coffee and cake in one of the city’s most restful spaces: a cemetery.

Berlin's old airport.

Dedicated to the European Sinti and Roma peoples murdered during the Holocaust.