The Wetumpka crater

A five-mile ring of hills just outside Wetumpka, Alabama, and one of the best-preserved marine impact craters on Earth. About 84 million years ago an asteroid roughly 350 metres across hit shallow coastal sea here; the shocked quartz and the crushed, overturned rim rock confirm it. Alabama calls it the state’s natural wonder and you can drive the rim without realising you are inside a crater until someone shows you the shape on a map. Mostly private land, so view from the roads and the marked overlook.