This long, dark tunnel is open to hikers, but those without lights are known to get confused even on the straight path.

Train debris from the deadliest avalanche in United States history can still be found in the ravine where so many perished.

The site of the Wellington avalanche, one of the America's worst railroad disasters.

All that remains of the Whittall mansion are the ruins of the formal garden and its pergola, dedicated to the late Matthew J. Whittall by his widow.

This secluded ruin was once a home for exotic plants.

This botanical garden boasts sculptures, industrial ruins, and an endorsement from the Dalai Lama.

This enormous sinkhole hides a secret world created from divine wrath.

Woven tree art gives this towering Australian woodland a touch of mystical whimsy.

Crooked windswept pines give this old forest an enchanted and magical look.

This enchanting natural park is a magical example of a temperate rainforest in Europe.

A brilliant turquoise lake in the mountains.

Granny Smiths and Fujis can both be traced back to Kazakhstan, where apples still grow wild.

For this chef, an active volcano is his oven.

The farthest northwesterly point of the British mainland is one of the most remote places in the Scottish Highlands.

A failed infrastructure project now owns this unique moniker.

A sea cave with a waterfall and Viking past

The remains of a 19th-century school and living quarters are perched atop a mountain surrounded by a thick tropical forest.

This river island in Sierra Leone is home to impressive biodiversity and the country's first community conservation program.

This remote Scottish isle is only inhabited by seals, birds, and the memory of a tragic settlement.

An abandoned Jazz Age dream home and con man's hideout in Death Valley.

The abandoned zoo enclosures offer a perfect place to experience the other side of the bars.

The one-time watch house for incoming ships at the Golden Gate now stands abandoned and hidden in trees.

Not truly a ship nor a building, the Navy's first and last "landship" is now abandoned due to clerical issues.

Secret Manor, a house full of legends, the least of which is the haunting of long-deceased ladies of pleasure.