Welcome in CruisersForum, seeleys
Yes, South Brittany is a bit crowded in summer. But it's generally possible to obtain a berth in
marinas, provided you arrive early enough. Sometimes, you will have to raft up, even on
mooring balls.
For example, that's the case in River Belon: there are 3 big
steel mooring buoys, between which you moor bow and stern, alongside with 2 or 3 other yachts.
Some very popular mooring areas are full by mid-afternoon. That's the case in Glénan archipelago. Depending on the tide, some moorings might also not be deep enough for 40' yachts.
It's the same for some
anchorages, e.g. on the coast of Belle-Île when the
weather is suitable. The other weekend, the anchorage where I intended to go appeared crowed. There were 4 yachts in the one I finally chose, another arrived after us.
Maybe we will meet when you come cruising...
Alain