In the basement of the U.S. Capitol Building is a hidden storage room full of ornate floor tiles leftover from the 1850s.

The privately owned cemetery that holds room for Washington's finest when they step down from life.

Perhaps the most scandalous statue of America's first president.

A museum cafe showcases Native American dishes and indigenous ingredients from across the Western Hemisphere.

The walls of the iconic dome are hollow and have a secret stairway.

The country's oldest continually-operated mini golf course lies hidden in plain sight, eclipsed by one of D.C.'s most popular tourist attractions.

A hidden gem on the lawn of the U.S. Capitol Building designed by landscape architect Frederick Law Olmsted.

A painfully obvious spy house sits right across the street from the Russian Embassy.

A plaque immortalizes the spot where the early American spy said his famous last words: "I only regret that I have but one life to lose for my country."

A B.Y.O.B. Mexican cantina lives inside one of the last tortilla factories in Brooklyn.

The home of aviation trailblazers, in a remote corner of the big city.

This Orthodox Church's exterior is rather unorthodox.

Here, exhibits come with a side of edible history.

This 220-year-old house is a reminder of New York City's Dutch past.

Set sail on a small scale.

The mass grave of a heroic Revolutionary War regiment sits below an empty lot near the Gowanus Canal.

These ornate manhole covers were used for a now-forgotten purpose.

A working monastery hidden away in Brooklyn once abutted the location of a former inebriate's home.

A replica of a 7th-century church hides in plain sight in the middle of the concrete jungle.

The only surviving sidewalk clock in Brooklyn.

A Ukrainian church canteen doles out hearty fare in an East Village basement.

Built just after the American Revolution, the oldest row house in New York City still stands in Chinatown.

Where infamous mobster and leader of Murder Inc. Albert Anastasia made his home.

A one-ton statue of Steve Rogers beautifies the entry to a Brooklyn Bed, Bath & Beyond.