The big flat at the base of these mountains is the Matanuska Valley. It’s where I live during the winter months and the home to the towns of Palmer and Wasilla. The Chugach and Talkeetna Mountains surround the Mat-Valley on three sides. To the West of the the Matanuska Valley lies the Susitna Valley which runs all the way to the Alaska Range. So, the general area in which I grew up is known as the “Mat-Su Valley” or simply “The Valley”. The two main drainages are the Matanuska and Susitna Rivers both of which run into Cook Inlet. That is a very abbreviated description for an area the size of Scotland, but hopefully it helps paint a picture of the local geography.
This photo was taken looking West. The Chugach Mountains are below me, the Alaska Range is on the far horizon, and the toe of the Talkeetna mountains is sticking into the picture from the right side.