96 Cobra never seem to warm up

Since I bought my 96 Cobra I noticed that the engine temperature is almost always cold (as in, as far left on the gauge as possible) even after driving on the freeway for 30mins. It looks like it's moving a little bit when driving for 30mins or more, so it does look like the gauge is working but even then it's still very far on the left side.

At first I thought it was a good thing that my car would never overheat, but now I realize that it also means that the engine never reach optimal running temperature.

Where on the gauge should it normally be when driving normally? And how long should that take?

I am guessing it's probably the thermostat that needs to be replaced.