The massive machine creates cracking displays of indoor lightning.

The bears may be gone, but their old cages can still be found.

Berthed at the Charlestown Navy Yard in Boston, "Old Ironsides" is the oldest commissioned warship still afloat.

Ralph Waldo Emerson spent two years living here decades before it became a Frederick Law Olmsted-designed park.

The Boston square dedicated to the dark poet who was born nearby.

A morbid secret lies hidden within the beautiful walls of the Boston Athenaeum.

One of the oldest used bookstores in the U.S. has been selling antiquarian treasures since 1825.

Two thousand artifacts from around the world collected by one woman who loved to travel.

This upscale streetwear store is hidden behind a fake Snapple machine in the back of a deli.

A beautiful Victorian-era cemetery, complete with a miniature village.

This Boston medical museum features the skull of the famous medical case of Phineas Gage.

This industrial area was the dumping ground for massive amounts of trash, some of which washes up as tiny bits of sea glass.

Race through the maze, get your name on the sign.

This ancient Hawaiian henge may have been an early star chart.

The air force base preserves its scars from the Japanese attack on Pearl Harbor.

This ruined fort and statue are a testament to the last king of Kaua‘i’s savvy diplomacy skills, which briefly brought Russians to Hawai‘i.

A once-glowing grotto at the bottom of Waikapalae Wet Cave.

This narrow coastline trail through the dense Kauai wilderness is among the most beautiful and dangerous in the world.

Submerged lava formations create incredible waterworks.

A unique set of caves that spits waves back out into the ocean.

A series of waterfalls and pools that flow through the 'Ohe'o Gulch and into the ocean.

This legendary urban waterfall creates a dazzling display of rainbows.

This unusual lava tube spouts seawater during high surf.

Football field-sized microalgae production tanks on the Hawaiian coast create a stunning view from space.