Snorkel with Cape Fur Seals at Robberg Peninsula in Plettenberg Bay. Offshore Adventures is the only company in Plettenberg Bay that offers snorkeling with Cape Fur Seals in their natural environment. GET WET IN PLETT with Offshore Adventures. For extreme adventure, come on-board "Hooligan" and experience a high speed boat adventure, where the boat can reach a top speed of 110km/hr. Free diving at it's ultimate best, offered to you by Offshore Adventures. Experience unadulterated fun!