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

A pedestrian island in the middle of world-famous Times Square emits a strange (and purposeful) humming noise.

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

This cemetery has graves dating back to the 17th century, including the city's oldest carved tombstone and an ominous cryptogram.

Elevated freight railway turned wildly successful urban park.

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

This restored house is like a time capsule of the president's unconventional inauguration.

The site of William McKinley's tragic assassination is only marked by an underwhelming boulder.

Created by four famous men, the beautifully designed Buffalo State Asylum was resurrected as a hotel and art center, but still boasts a ghost story or two.

Solar powered Spectacle Island features all-green facilities.

This small shop walked so America could run on Dunkin'.

The homestead of American patriot John Adams.

From economic backbone of a community to deadly diving hole, these former stone quarries are now a park for rock climbers and graffiti artists.

This bridge was the birthplace of a unit of measurement based on a fraternity joke.

One of the now-less-hidden floral gems of the "Emerald Necklace."

A beacon atop a downtown building provides Bostonians with weather forecasts and baseball news.

This hotel was the site of major events in sports and radio history. It was also used as a detention center during World War II.

The last remaining 19th-century tenement from Boston's old West End neighborhood.

A centuries-old church stands as a testament to Boston's "father of architecture."

What was once a true peninsula has now been filled in, causing the water to recede and leaving many streetside "waterfronts" and landlocked "islands."

The world's largest piece of copyrighted artwork.

This parking garage was the site of what was - at the time - the largest cash robbery in history.

Millions of numbers carved in glass represent the tattoos forced upon victims.

One of the few remaining monuments dedicated to South Boston's Irish heritage.