Jarrangbarnmi is also known as Koolpin Gorge. It took about 5 hours from Parap including a stop for lunch. About 1 hour 30 from Mary river ranger station although you wouldn’t think so. The walks aren’t signposted very well so make sure you read the map. Fires are allowed. Collect firewood on the way though it shouldn’t be an issue. Permits only. The old fashioned smelly long drop toilets. Not too bad of a camp site, definitely something to do if you’ve seen most of Kakadu.