This railroad tunnel was once the longest in Massachusetts.

Once the largest gravity dam in the world.

Unlike other abandoned asylums this empty institution welcomes visitors, just don't go in the buildings.

This abandoned neighborhood is now a park filled with beautiful trees, wildflowers, and hints of its past.

Once the largest public hospital for the mentally ill was also surrounded by controversy.

No one really knows how these old hobby horses got here, but the herd keeps growing.

One of the smallest towns in the United States.

The only geyser in the state of Pennsylvania is caused by pressure from an abandoned coal mine outside of the ghost town Centralia.

An American flag was erected for every day that passed during the Iranian Hostage Crisis.

"Where the ducks walk on fish."

For decades, it has disappeared and reappeared as water levels rise and fall.

It would take 35 firetrucks to fill this enormous glacial pothole.

A mere dot on the map in the great north woods is the first place in America to vote in Presidential elections.

This site was once the largest ski jump tower in the world.

An unrecognized nation-state created in the 1820s to avoid taxes.

These towering spires and glowing walls are carefully crafted from hundreds of thousands of icicles.

One of the most scenic falls in Massachusetts has a history of death and grim legend.

This massive solar system model is sprawled out across Maine's suburban wilderness.

This 1,700-pound edible sculpture is way better than your average chocolate mousse.

A monument marks the beginning of the longest north-south road in the United States.

A giant telephone commemorates the last "crank" call ever made in the U.S.

The world's oldest and largest museum of mass transit vehicles.

This 150 foot seven-tiered cascading waterfall is one of the hidden gems of the White Mountains.

America's oldest archaeological site or a muddled case of wishful thinking.