In this 400-year-old hotel in Madrid, you'll find a comb in every room, an old clock, and maybe a ghost.

The oldest building in Madrid.

Known as the Casa de las Siete Chimeneas, this haunted 16th-century manor has a dark, mysterious past.

Order cookies baked by cloistered nuns in a 400-year-old monastery.

This macabre masterpiece of a mural is one of Francisco Goya's "Black Paintings."

The only urban monument in the world designed by the great surrealist painter Salvador Dalí.

The morbid items in this small and hidden museum are not for the weak stomached.

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

This modest post office sits on the site of H.H. Holmes' famous murder castle.

Dodge prohibitionists and slide through the telephone booth in Crif Dogs.

Great place to have a drink and a bite to eat in an atmosphere laden with New York's Bohemian past.

Rome's semi-secret peephole vista is also a former Crusader stronghold.

2300-year-old Roman road connecting the empire.

One of the largest-ever mental hospitals now sits abandoned, surrounded by 25,000 unmarked graves.

This folk art compound was built by a fortune teller on the advice of three people from the future.

Thousands of well-dressed mummies below a monastery.