The purpose of sailboats is an obvious one; using the power of wind in their sails, they move across the water from destination to destination. The water is crucial in this equation. They're significantly less good at moving through ice, as Sir Ernest Shackleton and his ship, the Endurance, found out in 1915.
It had been a bad trip for Shackleton to begin with; he'd been beaten to the South Pole by Roald Amundsen and his team. On the return home, the Endurance became trapped by packed sea-ice, which eventually lifted the ship clean out of the water and froze it in place, as we can see here. Amazingly, the crew survived by camping on the ice for 18 months before jumping on life rafts in desperation, eventually reaching an inhabited island. The Endurance had no such luck; eventually the density of the ice became too much for it, and it was destroyed by the crushing force.