La Spezia has a huge marina and port. There you may observe fancy yachts and sailing boats as well as some other more modest, but nonetheless less enjoyable. Also, there are some fishing boats on one side of the port.
In La Spezia there are regular boats that take visitors to Portovenere and Cinque Terre, as well as Lerici. Visiting Corsica (for a few days) is another option, as there are boats departing from La Spezia to the French island.