This massive steel pyramid can be entered by a set of jagged steps that let visitors stand in its heart.

The Bauhaus-style former industrial complex is considered the world's most beautiful coal mine.

This strange building looks like a medieval fortress crashed into a 1960s Brutalist office block.

No need to strap in for a "ride" on this walkable roller coaster.

An elegant chandelier hangs over this ancient sewer chamber, now open for concerts and public tours.

The largest mosque in Germany.

A poignant mural honors the heroic teenage non-conformists who took on the Nazis and paid the ultimate price.

A long spiraling walkway winds through the woods, and around a copper beech tree at the center.

In 1830, cemetery workers in Cham unearthed a chamber housing thousands of skeletal remains from the 13th century, which can still be viewed today.

A former Latvian headquarters of the brutal KGB secret police is now open as a grim reminder of their atrocities.

This statue is dedicated to the animal cosmonauts that perished during space flight experiments.

This "floating railway" is one of the world's oldest monorail systems.

High winds can make this one scary landing.

New Zealand's only running funicular railway.

Taumatawhakatangihangakoauauo tamateaturipukakapikimaungahoronuku pokaiwhenuakitanatahu.

The last remaining Hakka cemetery in Singapore.

A disused quarry turned lake in the middle of a residential district.

From prostitutes to soldiers to business men, the dead in this graveyard are a microcosm of Singapore's history with Japan.

Singapore's last surviving traditional village is hidden among giant skyscrapers and modern infrastructure.

This house is one of the most colorful in the country, and is the last remaining example of a historic villa.

Thousands of well-dressed mummies below a monastery.

This electric green sulphur lake in New Zealand looks like a cartoonish radioactive dump site.

One man's dream has turned into this naturally growing chapel made of almost nothing but trees.

A tunnel once abandoned now thrives with graffiti art as an off-limits makeshift gallery.