This staircase in a lush tropical grotto was built by enslaved laborers and renamed to honor Queen Victoria's role in ending slavery in the British Empire.

A monument to a beloved aquatic folk hero in the Irish town of Dingle.

Ireland's most remarkable collection of these curious cone-shaped houses is worth the buzz.

The gorgeous library at Trinity College is home to remarkable treasures of Irish identity.

The somber sculptures commemorating Irish Famine on the river Liffey in Dublin.

A particularly disconcerting tribute to Irish martyrs.

One of Ireland's most infamous prisons for rebels including men, women and children.

The last remnants of Fort Pitt also hold the distinction of being the oldest structure west of the Allegheny Mountains.

This quarter-mile tunnel under the Bluff in Pittsburgh bends at a 45-degree angle.

Color-coded signs direct drivers on a network of routes designed to avoid Pittsburgh traffic.

There aren't too many operational funiculars around, but Pittsburgh has two!

The largest university building in the West is a gothic masterpiece containing dozens of theme rooms based on different countries.

Sections of the iconic limestone columns have been left uncleaned as a reminder of the city's polluted past.

A model of a dinosaur that was named for Andrew Carnegie stands outside the museum that also bears his name.

The last funhouse of its kind, where guests enter through the mouth of an 80-year-old blue whale.

"Where the ducks walk on fish."

A living maritime paradox still floats in the same lake where it was built and resurrected... or was it?

Explore this unspoiled peninsula with 11 sandy beaches and 13 miles of hiking and biking trails (keep an eye out for soaring bald eagles overhead).

A local prank turned town icon.

This mobile theater show highlights the story of Hershey through fun facts, unique stories, and plenty of candy samples.

Themed gardens, a conservatory, and a rose named for Milton Hershey, all overlooking Hersheypark.

This extraordinary Depression-era expenditure was modeled after a postcard of a Mediterranean hotel.

A little marble compass above George Washington's (empty) tomb in the Capitol marks where D.C.'s four quadrants intersect.

The 5.5-mile ring of steel posts around the Capitol Building is one of the largest (and most uniform) of its kind in the world.