Our current boat is a Southerly 49 - a "swing-keel" sailboat that draws less than 3 feet with the keel up. This summer we took the mast down and went right across France via the Seine, Paris and the small locks to the Med - 179 locks in all.
However she is also a good offshore sailing boat and also this past fall we took part in the ARC Rally for Cruisers crossing the Atlantic in just 15.5 days. With the keel all the way down we draw 10'4". The keel weighs in at a hefty 2,000kg so she sails quite well upwind. For the tradewind crossing with the ARC we swung the keel much of the way up. Then the boat really likes going downwind since the center of lateral resistance moves aft as you swing up the keel. I think we were one of the very few boats in the ARC that could do both the French canals and a transatlantic passage in 15,5 days... but I'm biased