The source of the river was on top of a mountain but it was covered with a thick impenetrable fog. My teleportation spot was next to a lake at the bottom of a waterfall that came from the said mountain. Most likely, all this water came from a place created by another powerful spatial magic.
The water was really clear and fresh compared to normal water you can get in any human town. I looked into the bottom of the lake and everything under the water was beautiful and lively. I got a little creeped out for some reason. I suddenly remembered that it totally looked like those bodies of water back in earth that was rumored to have a guardian. Those places like to take the lives of a couple of visitors every year as an offering of some sort.