During World War II the Thorp building was guarded by the OSS, FBI, and US Navy because of the top-secret bombsight being produced there.

This ambitious attraction was the brain child of a lake resort impresario, and built by the WPA.

A giant granite cross remembers missionary Father Frederic Baraga, and his safe passage across an angry Lake Superior.

A spooky defunct railroad tunnel now part of a sprawling trail.

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After four years of grasshopper plagues, this chapel was erected as a plea to God to make them end.

A 115-year-old restored German dining hall awaits those who venture beneath the Minnesota State Capitol.

The fungus-shaped vintage gas station has served multiple purposes over its lifetime, and now serves ice cream.

This rare vessel mixed luxury with labor before being converted to a museum and sometimes haunted maze.

America's silhouette includes 100 square miles of wilderness jutting into Canada thanks to an old mapmaking error.

An amazing collection of sculptures and art.

Minnesota's oldest and deepest mine is now an underground physics laboratory.

Duluth mineral magnates built this charming art deco lodge to be their private clubhouse.

This posh mansion began as a family's estate and ended as the site of a murder ripped from the pages of a pulp novel.

The home where a lovestruck Fitzgerald wrote his first published novel, "This Side of Paradise."

These curious caverns have been home to mushrooms, gangsters, and disco.

Originally built to monitor fishing, this Victorian tower now educates visitors about the local salmon industry.

These moss-covered medieval ruins tower atop the smallest of Ireland's Aran Islands.

The severed head of a 17th-century Irish martyr lies within an intricate golden shrine.

An ancient holy well said to be used by the patron saint of sailors and travelers, lost in the boggy west of Valentia Island.

This pub built its reputation pouring post-shift pints for employees of the cemetery with which it shares a wall.

The house where the writer spent his formative years.

A stunning Victorian abbey and walled garden on a lakefront.