I'm a beach fan, but not a sit on the beach for hours at a time beach fan... more of a walk the beach whenever possible or sit for a few minutes every day to breathe in that salty air. I've mostly been to beaches in New England, Florida, Puerto Rico, eastern Canada (NB and PEI), Ireland, and France, as well as one great lake as a child (Huron.) I can't pick a favorite. My beach is sandy (a rarity in northern New England) but I also love the scenery of rocky beaches, and I love cliffs over beaches.
I live in a beach town- I'm less than half a mile from a popular New England beach, so I'm there often EXCEPT in the summer. It's too crowded and I don't do well in sun! I do try to at least walk on the beach several times a week most of the year. I actually sat in my beach chair for a while on Sunday but it was too cold to really enjoy it.
I grew up spending summers split between the Cape Cod beaches and the family camp on a lake in northern New England. I've never liked swimming in lakes, but I do love kayaking and other boating, and yoga on the dock. I prefer swimming in salt water but I don't actually go into the ocean a ton... New Year's Day for a polar plunge at my beach and then maybe once or twice during the summer (again, too crowded!) and when I'm traveling somewhere with warm water beaches. The coldest beach of my childhood was Scusset (one end of the Cape Cod Canal.) We went there to play and walk the rock jetty but never to put more than a toe in the water.
I recently visited some Bay of Fundy beaches... WOW. Absolutely incredible to see the tidal changes and probably one of my absolute favorite places in the world.