At Wisemans Ferry, on a broad green bend of the Hawkesbury River northwest of Sydney, houseboats have been hired for more than forty years. The range runs from the two-berth Aquavan through six-, eight-, ten- and twelve-berth boats to the Five Star and Ultimate Spa vessels, which carry heated ten-person spas, full kitchens and en-suite cabins. No special licence is needed; a safety briefing sends you off to handle the boat yourself. Day boats and kayaks round out the fleet for shorter outings.