The Kiama Coast Walk is the main active reason to base a day around Gerringong. The full route runs about 20 km from the Minnamurra River through Kiama to Werri Beach, but the southern section from Loves Bay to Gerringong is the one to choose if you want open pasture, exposed cliffs, and a proper sense of distance.
The walking is not technical, but the route is exposed. Carry water, avoid the hottest part of summer days, and check local advice after heavy rain when Werri Lagoon can interrupt the final approach.