[3] The park is located in Southwestern Ontario, on an 8 km long crescentic sand spit extending into Lake Erie.

The name of the park comes from the French words "ronde eau" or "round water" which describes the shape of the harbour sheltered by the peninsula.

[10] A narrow sand spit extends west, sheltering the marshes and bay, and nearly reaching the town of Erieau.

[3] The initial regulations governing Rondeau prohibited settlement, grazing, and most logging, and allowed for camping under permit and a renewable lease policy for cottages.

Rondeau is one of only two Ontario provincial parks with private cottage leases on publicly owned land.

The club continues to operate during July and August teaching sailing, windsurfing, canoeing, and swimming to area children.

[18] Rondeau has a variety of habitats, including sandy beach, dunes, prairie, oak savannah, Carolinian forest, woodlands sloughs, a large marsh, and productive shallow bay.

[21] A variety of nationally and provincially threatened or endangered species are found in the park, such as eastern spiny softshell and nodding pogonia.

[20] Although controversial, culls to control deer numbers are held on a regular basis, in recent years involving members of the Delaware Nation at Moraviantown.

[23] Park facilities include 262 developed campsites, six hiking trails, picnic areas, a boat launch, and a visitor centre with interpretive displays and programming.