The Polish capital has had a deep connection to its guardian mermaid for almost a millennium now.

This biographical museum honors the groundbreaking scientist at her birthplace in Warsaw.

The highest point in Maine is a grand gift to the state citizens that also happens to be one end of the Appalachian Trail.

A quarter mile off the coastal tip of Maine you'll find the "Beloved Island" of Franklin Delano Roosevelt.

This candy-striped tower is the farthest east you can go in the United States.

Known as one of the most climbed mountains in the world, this barren peak is permanently bald thanks to an anti-wolf fire.

This open-air spiritual sanctuary offers stunning views of Mt. Monadnock and provides a natural and peaceful environment for worship and meditation.

A dedication plaque on this Boston tunnel is a microcosm of a massive, controversy-laden construction project.

The colonial home of Paul Revere during the American Revolution.

The site of Paul Revere's historic two lantern warning.

Daredevil repair workers can worm their way out the access hatch, loop ropes over the apex and rappel down the monument.

The monument's pointy aluminum tip has been melted down by repeated lightning strikes.

Look closely and you’ll notice that the color changes a third of the way up the tower.

Thomas Jefferson's estate is home to hundreds of varieties of historic fruits and vegetables.

Caves that can't seem to quit producing the remains of prehistoric humans.

This beautiful, historic church looks like something out of a simpler past.

The picturesque birthplace of Icelandic democracy is drenched in the blood of its brutal past.

If a glacial river suddenly diving into a sheer chasm via a dramatic, multi-stage waterfall isn't peak Iceland, it's certainly close.

This valley of hot springs and boiling mud pots is home to the record-holding "Geysir," which originated the English word.

Inside this Icelandic greenhouse, geothermal energy keeps tomatoes warm and growing.

One of the tallest buildings in Iceland, and perhaps, the most visually impressive.

Walk along the medieval fortifications that have been protecting Tallinn since the 14th century.

These enormous, stern-faced statues greet visitors with lanterns, and sometimes costumes.

This irregularly shaped sea fortress has defended not one but three different sovereign states.