In April 2014, scientists reported finding evidence of the largest terrestrial meteor impact event to date near the area. They estimated the impact occurred about 3.26 billion years ago and that the impactor was approximately between 37 and 58 kilometers (23 to 36 miles) wide. The crater from this event, if it still exists, has not yet been found. In May 2019, extraterrestrial organic materials in 3.3-billion-year-old volcanic rocks was found at Makhonjwa Mountains.