The beach is the engine of summer in Cobourg. A wide arc of fine pale sand runs for about a kilometre west of the harbour, with shallow swimming water that warms early in the season and a low boardwalk along the back. On a hot July weekend it fills with Toronto day-trippers — the town's population briefly doubles — but the morning and evening hours are still quiet enough.
Behind the beach, Victoria Park has shaded picnic tables, a bandstand, washrooms, and the small refreshment stands that run all summer. The Sandcastle Festival in early August draws competitors and crowds from across the province; the rest of the summer the beach hosts kite-flying, lifeguarded swimming, and the slow drift of the seasonal lakefront crowd. The harbour east of the beach has a working marina, with a paved walkway that loops out to the breakwater for a long view back at the town.