Oklo Mines – the only natural nuclear reactor

Flooded mine in Mounana, Oklo in Gabon

The only known site on Earth, where natural nuclear fission has taken place approximately 1.7 billion years ago in some 16 closely located sites. The evidence of this has been testified through an unusual composition of uranium, neodymium, ruthenium, and other materials.

Daikoku Sulfur Cauldron

Daikoku Sulphur Cauldron at the moment of discovery, Northern Marianas

A unique pool of liquid sulfur at the summit of a submarine volcano, one of the few in the world.

Usterling Growing Rock (Johannisfelsen)

Usterling Growing Rock, Bavaria

Almost unique natural landmark – a naturally formed tufa wall with a stream flowing along its upper rim and depositing further extension to this cliff. Wall is some 40 – 50 m long and up to 5.4 m tall.

Lake Bonney – lake in Antarctica with laughing gas

Lake Bonney from satellite, Antarctica. Inscription "Lake Bonney" is on the eastern lobe.

Frozen lake with unique geochemistry. The east lobe of the lake is saturated with nitrous oxide – "laughing gas" and dimethylsulfoxide. Another part of lake is rich with dimethylsulfide – possibly produced by microorganisms.

Giant Forest, California

Giant Forest with General Sherman tree - the largest tree in the world in the centre

Unique forest with stands of giant sequoia trees (Sequoiadendron giganteum) – the largest trees in the world. This is the easiest to access sequoia grove but also contains the largest trees – five of the ten largest trees on Earth are located in this grove. Area – 7.6 km2. In California are located several more notable groves of these giant trees.

Multnomah Falls

Multnomah Falls, Oregon

Very tall waterfall with three main drops, 194 m tall. A picturesque bridge between below the tallest drop.

Kawah Ijen

The blue fire of Kawah Ijen, Indonesia

Turquoise-colored, extremely acid lake with a diameter of 1 km. Acidity – 0.5 pH. Nearly pure deposits of sulfur are located in the caldera. The burning sulfuric gas creates a very impressive blue flame in the night.

St. Magnus Cathedral in Kirkwall

St. Magnus Cathedral in Kirkwall, one of the best examples of Norman architecture

Northernmost cathedral in the British isles, an excellent example of Norman architecture. Construction started in 1137, built over 300 years. Dungeon – prison under the church.

Virginia Falls (Na’ili Cho)

Virginia Falls, Canada

Last primeval large waterfall in North America. Here the powerful South Nahanni falls 90 meters, the width of falls reaches 259 m. Some 120 m tall spire of rock – Mason’s Rock – stands in the middle of the falls.