Big Amazing Hole on Earth ! amazing picture

kimberley big hole - south africa
Kimberley is a town in South Africa, and the capital of the Northern Cape,
In 1866, Erasmus Jacobs found a small white pebble on the banks of the Orange River, on the farm De Kalk leased from local Griquas, near Hopetown. The pebble turned out to be a 21.25 carat (4.25 g) diamond. In 1871, an even larger 83.50 carat (16.7 g) diamond was found on the slopes of Colesberg Kopje by Esau Damoense, the cook for prospector Fleetwood Rawstone's "Red Cap Party," who was sent to dig on the hill as a punishment for being drunk. This find led to the first diamond rush into the area. As miners arrived in their thousands, the hill disappeared, and became known as the Big Hole. A town, New Rush, was formed in the area, and was renamed to Kimberley on 5 June 1873, after the British Secretary of State for the Colonies at the time, John Wodehouse, 1st Earl of Kimberley. The British, who had control of much of South Africa, were quick to annex the area of the diamond mine, which became the British colony of Griqualand West. The Boers were upset by this, because they wanted it to be a part of the Orange Free State as it lay inside the natural borders created by Orange and Vaal Rivers.

monticello dam

Monticello Dam is a dam in Napa County, California, United States
Monticello Dam was constructed between 1953 and 1957. The dam is a medium concrete-arch dam with a structural height of 304 ft (93 m) and a crest length of 1023 ft (312 m). It contains 326,000 cubic yards (249,000 m³) of concrete.

the outside of the dam

Monticello Dam was constructed between 1953 and 1957. The dam is a medium concrete-arch dam with a structural height of 304 ft (93 m) and a crest length of 1023 ft (312 m). It contains 326,000 cubic yards (249,000 m³) of concrete.

view of monticello dam spillway

The dam is notable for its classic, uncontrolled spillway with a rate of 48,400 cubic feet per second (1370 m³/s) and a diameter at the lip of 72 feet (22 m). The eerie appearance of the spillway in operation attracts visitors.

bingham canyon mine, utah

Bingham was a city formerly located in southwestern Salt Lake County, Utah, in a narrow canyon on the eastern face of the Oquirrh Mountains,
This is supposedly the largest man-made excavation on earth. extraction began in 1863 and still continues today, the pit increasing in size constantly. in its current state the hole is 3/4 mile deep and 2.5 miles wide.

great blue hole, belize

The Great Blue Hole is a large underwater sinkhole off of the coast of Belize. It lies near the center of Lighthouse Reef, a small atoll 60 miles from the mainland and Belize City. The hole is circular in shape, over 1,000 feet across and 400 feet deep. It was formed as a limestone cave system during the last ice age when sea levels were much lower. As the ocean began to rise again the caves flooded, and the roof collapsed.^[1]

On-shore caves of similar formation, as large collapsed sinkholes, are well known in Belize.^[2]

This site was made famous by Jacques-Yves Cousteau who declared it one of the top ten scuba diving sites in the world. In 1971, he brought his ship, the Calypso to the hole to chart its depths. ^[3] Investigations by this expedition confirmed the hole's origin as typical Karst limestone formations, formed before rises in sea level in at least four stages, leaving ledges at depths of 70, 160 and 300 feet. Stalactites were retrieved from submerged caves, confirming their previous formation above sea level. Some of these stalactites were also off-vertical by 10° - 13° in a consistent orientation, thus indicating that there had also been some past geological shift and tilting of the underlying plateau, followed by a long period in the current plane.

Cousteau also investigated Andros island^[3] and described similar Karst cave features, although less spectacular than a collapsed blue hole. Finding Karst topography in this location supports the possible explanation of the nearby Bimini Road as a natural limestone pavement.

at surface level the near perfectly circular hole is 1/4 mile wide, the depth in the middle reaching 145 metres. obviously the hole is a huge hit with divers.