I've seen a few marinas around the world and this place isn't shamed by any of them.
For adults there are many boutique shops with a fair bit of variety and a very large range of eating options, not all of which are cheap. There are boats to look at, a sheltered swimming beach (though there can be little stinging jellyfish on odd occasions) and a hotel (pub). Boats can be chartered for whale watching or fishing. There are many attractions for children with a waterslide park, trampolines, high ropes and more. I go quite often and it really is a lovely place. Parking can be difficult. Best to go for the free northern carpark and walk the short distance across the bridged area to the main section. That way you can at least get in and out easily.
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