This iron and wood Civil War city-ship was the first vessel to be sunk by an electrically detonated torpedo.

"X" marks the spot of an echo chamber in the middle of a plaza.

The largest ancient burial mound in Ohio.

The highest point in Indiana is curated by an Eagle scout but may be in danger of losing its record to a nearby garbage pile.

The largest earthwork effigy in the world.

These sub-farmland caves are home to a majestic stalactite known as the "Crystal King."

In this relatively flat state the highest point is an honored place.

An office built to look like a giant basket.

Georges Seurat’s pointillist masterpiece has been recreated in Ohio in topiary form.

The inventor of a number of hybrid corn species is immortalized with a field of giant corn.

This presidential tomb was not dedicated until years after Harding's death due to personal controversy.

A gas station has taken the place of the home of the 19th American President.

One man’s vision of living among dinosaurs credits Jesus Christ as the engine of biological evolution.

Strange physical sensations and optical contradictions keep visitors coming back for more.

The fifth-longest suspension bridge the world, connecting one Michigan peninsula to another.

Take a drunken tour inside the world's largest known geode.

Deep scars on the earth left by the Ice Age.

The world's tallest doric column is this Ohio monument to a naval victory in the War of 1812.

The only surviving prototype for Buckminster Fuller's house of the future.

This massive airship factory is so large that it has its own indoor weather.

Memorials and tributes scattered across the university grounds remember a famous national tragedy of the Nixon era.

The only presidential monument to display a late POTUS's actual casket.

The angel of death appears to weep black tears at this grave marker.

The heroic sled dog of the 1925 serum run is preserved in taxidermy.