Every piece of nature that is not desert seems to be called a Wadi, and to be honest we still did not know the exact meaning 🌴.
So, here it goes. A Wadi is like a dry riverbed, a channel or low point in the landscape. Normally it is mostly dry, except for when it rains. Then the rain from a larger area can quickly collect into the Wadi.
Since the ground is typically dry and hard, this can even result in a flash flood. So, even though the Wadis are typically the most scenic spots, you have to be careful when camping there.