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

Yo, Adrian!

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

Tour the dark and beloved poet's former cobwebbed basement, which may have inspired "The Black Cat."

A layered tribute to the work of mosaicist Isaiah Zagar.

World's first "penitentiary," meant to be humane, drove men insane.

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

The official Presidential Residence of Los Pinos became an emblem of Mexico's opulence and presidential corruption.

Beneath the most controversial monument in Mexico City is a cultural center that exhibits only digital art.

Many people don't realize there’s a lot going on in—and below—the world’s tallest triumphal arch.

A small pack of an ancient, hairless breed of dog once believed to guide souls through the underworld lives on its grounds.

This incredible college library is a visual masterpiece of mosaic art. It also looks kind of like a giant boombox.

This strange sculpture of a menacing skull surrounded by sun rays was discovered at the foot of the Pyramid of the Sun.

Where layer cakes tower above one’s head and there is never a shortage of icing.

The only castle in North America to ever house European sovereigns.

This Dutch Colonial home is the oldest remaining farmhouse in Manhattan.

The most confusing clock in New York.

Commemorating the spot where the famous scientist fed his pigeons.

A Victorian cemetery in the heart of Brooklyn remains a popular mecca of morbid curiosity.

This historic address is home to the beloved ball and is an almost totally empty building among the most expensive real estate in the world.

Everyone from Mark Twain to Teddy Roosevelt has a pipe hanging from the walls of this historic chophouse.

Visit the monolithic tomb of America's most famous general.

The former hotel where Tesla invented the radio.

This mosaic dedicated to John Lennon was tended for years by a Beatles super-fan.