Read between the lines of the subway map to find the hidden abandoned Civil War fort.

The former estate of the Guggenheims, part of the opulent Gold Coast that inspired the Great Gatsby.

An abandoned Gold Coast-era mansion once intended for the exiled ruler of Albania, who never arrived.

A town trapped in time - 1958 to be exact.

Where a staggering 747 ships were constructed during World War II.

One of few lasting examples of the brief octagon craze that developed into folly.

A brooding mansion of clinker brick stands out among the Victorian houses of Pacific Heights.

Half of a house.

Only hotel where you can legally launder money.

Nestled in the heart of San Francisco’s bustling Financial District stands a unique homage to the Mayan and Beaux Arts.

27-room home built with the fortune of a sugar magnate.

A curious fountain that has no water and includes Satan, a crab, and 9 giraffes.

A speakeasy takes on Chicago's drinking culture.

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

The highest point on the island known for buildings that touch the sky.

A Manhattan Episcopal church with an eerie underground crypt.

Largest Roman Catholic church in North America.

A haunting tribute to pioneering photographer Clover Adams.

The oldest house in Manhattan is now a museum that remembers the home's sordid history of scandals, vice-presidents, and ghosts.

The site of the climactic scene from the classic horror film is now a historic landmark.

The high point on the 16th president's eponymous roadway is marked by a massive version of his head.

The mummified heart of a saint lives on in this church—after a brief hiatus when it was stolen.

Some of the saint's blood and bones are said to reside in Dublin.

The oldest public library in Ireland.