Two little boys have arrived dressed as pirates. Metal bars rise at intervals, interspersed with non-slip panels, to safely aid their climb, but the steep gradient is deceptive. At the top, where the gangplank bridges the gap between dock and deck, it's suddenly a hell of a long way down.
Although the harbour is as flat as any floor, there's enough gentle movement for the little one to lose confidence at this crucial juncture. His sea-legs freeze. "I can't," he says in a tiny voice. The ship's medic, Jules – one of the many crew doubling as tour guides – extends an arm and, with encouraging words and a smile, shepherds him on board.
Like scores of people, the boy is on the Sam Simon for a free tour. Open to the public (in December) for the first time, the latest addition to the Sea Shepherd Conservation Society's fleet is docked in Hobart ahead of its imminent departure to Antarctica.
Sea Shepherd is famous for its anti-whaling actions against the Japanese in the Southern Ocean. Each summer, a predominantly voluntary crew comes from around the world to work on the vessels and, ahead of each campaign, the members open up these ships when in dock so their supporters and other interested parties can have a look.
The Sam Simon – named after one of The Simp-sons' creators, who donated the money to buy it – is at Macquarie Dock 1. The ship's first mate, Adam, takes us on this tour, around the decks and down below.
There's the galley, scullery and mess. We clamber up step ladders and squeeze into low, narrow corridors for an insight into just how different, and confined, life at sea would be. We line up in front of the bridge.
"You can see inside, all the controls are labelled in Japanese; we have translations above them in English," Adam says of the ship that was originally used by the Japanese for research.
The facts are fascinating (the ship uses four tonnes of fuel a day) and the tour ends with a short video detailing Sea Shepherd's other marine-conservation campaigns.
Apart from the Sam Simon, the waterfront offers more than enough options to fill the rest of the day. Like Hobart itself, the harbour is conveniently compact. I have breakfast at T42°, beside the yachts in Kings Pier Marina. Lunch is at Mures Lower Deck, with a view of fishing boats, and I finish the day in the bar at the Grand Chancellor Hotel, the pick-up point for the airport shuttle, which overlooks Victoria Dock. A stroll between each takes perhaps a minute.
My marine instincts have been stirred, so in the afternoon, I'm back on the water. Ferries and cruises take visitors to Wrest Point; Port Arthur; the Museum of Old and New Art; or eco-tours to Bruny Island.
I set sail on the Lady Nelson. A replica brig, it offers 90-minute sojourns along the Derwent for $25. (Another tall ship, the Windeward Bound, offers a three-hour trip, including lunch, for $75).
We use engine power to exit the marina but, once on the river, the crew launch into action: orders are shouted, sails hoisted, elaborate knots frantically tied and untied, and we are sailing. It's windy, cold, and we cop a bit of sea spray, but unlike what the Sam Simon is heading into, there's not an iceberg in sight.