The Rocky River Mouth is located within Flinders Chase National Park on Kangaroo Island, South Australia. It is primarily referenced as a hiking destination along the Kangaroo Island Wilderness Trail and the Snake Lagoon Walk, with the trail leading directly onto a sandy beach at the river's outlet to the Southern Ocean. This beach provides the primary access point for paddlers. North Coast Road runs past the beach, providing parking and beach access. The carry distance to the water is short, as the trail deposits you directly onto the sand. The overall character is that of a wild and rugged coastline on the island's south-western coast, exposed to the full force of the Southern Ocean. The beach is flanked by hills and cliffs, and a notable cave is present on an adjacent hill. The area is remote, within a national park, and the vibe is one of pristine wilderness.

Paddling conditions are heavily influenced by tide and swell. A low tide route crosses the sandy beach, while a separate high tide trail is used when the beach is covered or when waves and swells are high, indicating significant tidal variation and potential for strong surf and shore-break at the mouth. This exposure makes it a challenging launch and landing site suitable only for experienced paddlers comfortable in dynamic ocean conditions. The best time for paddling would coincide with calm seas and low swell periods, typically during the austral summer months. The river itself may be pooled or not flowing at times. From this launch, paddlers can explore the dramatic coastline, including views of the cliffs above the river mouth and access to nearby Maupertuis Bay. The area is known for its unique coastal plants and wildlife, including kangaroos. Facilities are limited to the context of a national park wilderness area; the Snake Lagoon campground is nearby.