Secluded places for intimate activities?

My husband and I are feeling frisky and looking to spice things up. We want to try having sex in outdoor secluded places. At the same time we still want to be smart about the chosen areas.

Any recommendations of good areas in Houston for car sex where we won’t get caught? Also open to recommendations in the suburbs, or state parks, etc.

In addition, anyone have suggestions for outdoor secluded areas (not in the car) like in nature or the woods for future escapades?