Cape Town - The list of things to do in Mossel Bay is about to get faster and louder with the opening of what is being called the “world’s longest over-ocean zipline” in the next few days, weather permitting. The one-of-its-kind facility adds to the existing adventure tourism offering in the area, with as many as 8,000 to 10,000 zip-line users attracted per annum, drawing on the growing extreme adventure tourism market.