Where on Mars?

For some time now, I’ve been puzzling over where to place Dawn Colony on the surface of Mars. Here is the description of the landscape around the colony from Scratching the Surface:

Sally pointed out the featureless plain that stretched away on one side of the town until it met a range of jagged mountains far off in the hazy distance. Under that plain was the water that made life in the colony possible. That water was used not just for drinking and watering the Forest, but for the generation of the air they breathed and the fuel for the rovers and rockets, and for the bricks used in the surface buildings, and in the plastics used everywhere in the town.

In the other direction, volcanic hills rolled chaotically off into the distance. She explained that the ancient volcanic activity under those hills had created the network of caverns used by the colonists for habitation.

So, I need a large plain with water or ice beneath, bordered by volcanic hills that include lava tubes on one side and a mountain range on the other. It also has to be low-to-mid latitude for optimal weather, and low elevation for optimal UV protection from the meager atmosphere. This is pretty specific! Each of these aspects exists on Mars, but will I be able to find a location that shares them all?

I haven’t had a chance to dig into this dataset, but hopefully it will help me find where on Mars these kids will grow up.

https://www.usgs.gov/center-news/caves-mars