From Walt Dated World website:
This attraction was also known as the Plaza Swan Boats. It opened May 20,1973. There were 15 boats that each held 30 passengers and it reportedly required two cast members to pilot them. There were two different loading docks that were used at various points during the boats' lifetime. One was located by the area that is now the outdoor terrace seating by the Plaza Restaurant. The other was located to the right of the castle toward Tomorrowland.
Swan Boats required a D ticket and sailed around the moat of the central hub and circled around the Swiss Family Island Treehouse in Adventureland. The boats only operated during peak park periods and closed for good in August, 1983. One reason that may have contributed to their demise were mechanical and navigational problems with the boats.
Contrary to popular belief, Disney World did not donate the Swan Boats to the city of Orlando. They have also have not been relocated to the Swan Resort. The swan-shaped boats that are there are two person paddle boats. The former entrance to the Swan Boat queue area is now part of a rose garden and the actual queue is sometimes available to sit at or for private events.