Part of Credit Valley Conservation, Terra Cotta C.A. is about an hour NW of Toronto. The area includes 1 lake, 2 ponds and several walking trails covering both water and forestland. We walked two trails, some of which loop back to the parking lot while others simply veer into woodlands. The Terra Cotta trail, which loops around Wolf Lake, is a converted roadway, so is easy for hikers of all experience levels. The McGregor Spring Pond trail starts out close by a pond and then takes you through easily navigated forest. Enough trails intersect that you can lengthen your route should you choose. We also took the A.F. Coventry Nature trail, which headed up a few more hills and across some valleys (via wooden bridges).
The park has several picnic areas and an information centre so families with children will have plenty to do. There is no wide open space though, so sports, etc. aren't feasible here.
As for wildlife, fishing is allowed during certain times of the year and in certain places. We saw a lot of dragonflies, crickets, frogs and one great blue heron.