The flower-shaped temple in Virginia aims to transcend the boundaries of the world’s religions.

A railroad tunnel that, upon its completion, was considered one of the engineering marvels of the modern world.

Thomas Jefferson's estate is home to hundreds of varieties of historic fruits and vegetables.

The ruins of this Thomas-Jefferson-designed mansion have been left to crumble since the Christmas Day they burnt down.

Ride the subways of yesteryear.

One of only two commuter aerial tramways in the United States.

Read a book next to a Midtown waterfall.

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

Just your average Marie Antoinette–themed speakeasy in an abandoned 19th-century subway tunnel.

Wall Street has a new heroine, a bronze statue of a small but fierce girl.

Mysterious 500-year-old tapestries depict a unicorn hunt.

This lower Manhattan bar is set up in an old bank vault that rests beneath a skyscraper that hides even more historic splendor.

The world’s oldest and biggest bookstore stocking only mystery, crime fiction, espionage, and thrillers.

Elevated freight railway turned wildly successful urban park.

This beautiful building in the heart of Manhattan's Financial District was empty for decades.

Amid the bustle and noise of the Financial District hides a secluded garden oasis above the city streets.

A beautiful and abandoned New York subway station from 1904, complete with chandelier.

The last of Philadelphia's wood-paved streets is now a landmark of terrible engineering.

The oldest surviving presidential residence in the United States.

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

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

This Philly landmark has a giant butterfly pavilion, three floors of insect displays, and withstood a $40,000 heist.

This little-known Revolutionary War fort is supposedly haunted by the ghosts of its past.

The oldest surviving botanic garden in the United States.