This charming colonial alleyway is one of the oldest continuously used residential streets in the U.S.

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

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

A layered tribute to the work of mosaicist Isaiah Zagar.

An abandoned cemetery lies in ruins as the surrounding forest swallows it whole.

America's most famous museum of medical oddities is home to the remains of Albert Einstein's brain.

The site of Austria's biggest concentration camp now honors its victims.

The solemn exterior conceals an opulent interior of this 17th century church.

An exquisite Baroque church in Vienna's old town.

A neo-Gothic church built to thank God for saving the Emperor of Austria from an assassination.

Vienna's giant wonder wheel had a starring role in one of the greatest noir movies of all time.

Giant WWII fortresses that fired 8,000 rounds a minute, now home to thousands of pigeons.

The personal charnel house of Anton Bruckner.

Baroque celebration of the end of the Great Plague of Vienna.

Op-art architecture designed for happiness.

The Habsburgs' royal collections of art and wonders.

Built to give thanks for the passing of a plague epidemic, this cathedral is a one-of-a-kind architectural hybrid.

A tropical paradise just a short trip from the opera house is filled with beautiful winged creatures.

The final resting place for the remains of 143 Habsburg royalty.

This "mathematical tower" was an observatory, early skyscraper, and place to reflect on all of nature and the cosmos.

The world's oldest known salt mine.

An Austrian house of bones filled with hundreds of intricately painted skulls.

The beautiful, ornate weather station is the most popular geocache in Salzburg.

Ugly 18th-century dwarf statues living in a perfectly landscaped Austrian garden.