Fascinating. There are a few other instances in the world, but surely none quite as vivid as "The Door to Hell". "The Door to Hell, as locals call it, is situated near the small town of Darvaz in Uzbekistan. Thirty-five years ago, geologists were drilling for gas when then encountered a very large cavern underground filled with a poisonous gas. They ignited the gas expecting it to burn off in a few hours. Thirty-five years later, the gas is still burning." [Edit: as barberio notes, it's apparently actually Darvaza in Turkmenistan]
Quite an episode, again, from RTD, in Turn Left - not exactly the lightest, fluffiest tale they've ever related. It's going to be a finale to look forward to.
An excellent piece of civic art, in Sweden, wherein rabbits on one side of a river are shown diving in, and on the other, pulling each other out. ^_^