The Vredefort crater is the largest verified impact crater on Earth, more than 300 km across when it was formed. What remains of it is located in the present-day Free State Province of South Africa and named after the town of Vredefort, although the crater itself has long since eroded away, the remaining geological structures at its centre are known as the Vredefort Dome or Vredefort impact structure. In 2005, the Vredefort Dome was added to the list of UNESCO World Heritage Sites for its geologic interest, the asteroid that hit Vredefort is estimated to have been one of the largest ever to strike Earth, thought to have been approximately 10–15 km in diameter. The bolide that created the Sudbury Basin could have even larger. The original crater was estimated to have a diameter of roughly 300 km and it would have been larger than the 250 km Sudbury Basin and the 180 km Chicxulub Crater. The craters age is estimated to be 2.023 billion years and it is the second-oldest known crater on Earth, a little less than 300 million years younger than the Suavjärvi Crater in Russia. In comparison, it is about 10% older than the Sudbury Basin impact, the crater site is one of the few multiple-ringed impact craters on Earth, although they are more common elsewhere in the Solar System. Perhaps the best-known example is Valhalla Crater on Jupiters moon Callisto, although Earths Moon has a number, geological processes, such as erosion and plate tectonics, have destroyed most multiple-ring craters on Earth. The impact distorted the Witwatersrand Basin which was laid down over a period of 250 million years between 950 and 700 million years before the Vredefort impact. These rocks form partial concentric rings round the crater center today, with the oldest, from about halfway through the Pretoria Subgroup of rocks around the crater center, the order of the rocks is reversed. It is thus possible that if it had not been for the Vredefort impact this gold would never have been discovered. This central peak uplift, or dome, is typical of an impact crater. The Vredefort Dome World Heritage Site is currently subject to property development, and local owners have expressed concern regarding sewage dumping into the Vaal River, the granting of prospecting rights around the edges of the crater has led environmental interests to express fear of destructive mining. The Vredefort Dome in the center of the crater is home to three towns, namely Parys, Vredefort and Koppies and also Venterskroon, Parys is the largest and a tourist hub, both Vredefort and Koppies mainly depend on an agricultural economy. On 19 December 2011, a license was granted by ICASA to a community radio station to broadcast for the Afrikaans-. The Afrikaans name Koepel Stereo refers to the dome and announces its broadcast as KSFM, the station broadcasts on 94.9 MHz FM. KMZ of 25 largest craters
Map of South Africa showing the location of the Vredefort Dome, the remains of a 2.020 billion year-old impact crater. The interrupted line circle, 300 km in diameter, marks the extent of the original crater.
Monochrome satellite view of the crater
A schematic diagram of a NE (left) to SW (right) cross-section through the 2020 million year old Vredefort impact crater and how it distorted the contemporary geological structures. The present erosion level is shown. Johannesburg is located where the Witwatersrand Basin (the yellow layer) is exposed at the "present surface" line, just inside the crater rim, on the left. Not to scale.