Loch an Eilein, Rothiemurchus

The castle ruins on that small island in the middle of the loch are what draw most people here, but honestly the walk around the water is the real draw. You're looking at roughly 40 minutes to an hour depending on pace, with Aviemore just a short drive south if you need supplies or a proper lunch afterwards.

It's a straightforward circuit path that winds through Rothiemurchus - mostly flat, well-maintained, though it can get boggy after rain. The castle itself dates back to the 14th century and sits completely isolated on its island, which is rather atmospheric even if you can't actually get across to it. In winter the loch can freeze solid enough for access, but that's rare these days.

Families with younger kids will manage it fine, though there's not much to do once you arrive - no café, no visitor centre, no play equipment. It's just you, the water, and the Caledonian pines. Walkers will appreciate the gentle terrain and the fact it doesn't demand four hours of your day. History buffs might feel slightly shortchanged by the distance - the castle's mostly rubble from here.

Stay at Dalraddy Holiday Park or Highland Glen and you've got something genuinely pleasant within spitting distance. Go early morning if you can; the light catches the water properly and you'll have the place nearly to yourself. Free, of course, and accessible year-round.