Ornate limestone building now filled with geologic specimens, and more.

Display that gathers the basic elements of the universe in one convenient location.

Bring your own cardboard to the slippery slopes of concrete hidden in a neighborhood park.

This mysterious hill seems to pull objects uphill.

A medical facility that has been kept frozen in time.

A hidden network of subterranean passageways lies tangled beneath Indianapolis' bustling City Market.

A 140-year-old castle with underground caves hidden in San Francisco.

Tenacious mummies survived dental problems, eternal entombment, and more than their fair share of devastating fires.

A promotional sun clock on the site of San Francisco's great raceway.

The final resting place of the Emperor of the United States and Protector of Mexico.

A whimsical antique shop with a strong air of mystery, filled with items from ages, and what feels like worlds, past.

Not merely a museum – but a whirring powerhouse that offers a subterranean peek into the heart and soul of cable car operations.

Its buzzing collection honors vibrator history.

A free, public museum dedicated to the fascinating science of sight.

One of few lasting examples of the brief octagon craze that developed into folly.

A brooding mansion of clinker brick stands out among the Victorian houses of Pacific Heights.

This private residence was the template for one of the most beloved television homes of all time.

The restored and active Victorian-era final resting place of San Francisco.

A monument to the love people have for their pets.

A 300-ship graveyard, with a few still visible at low tide.

This partially buried wreck is one of the most complete of its kind but is only revealed when the sea allows.

San Francisco's urban bison herd has persisted in the face of extinction, development, and disease.

A favorite haunt of dinosaur loving children and hallucinogen loving hippies alike.

The best place in the park to test out your throwing arm.