Dunure Castle & Harbour

A crumbling clifftop keep above a tiny fishing harbour on the Ayrshire coast, looking straight out at the granite dome of Ailsa Craig and, on a clear evening, the peaks of Arran. It's a compact, rewarding shoot: orbit the ruin with the harbour and rock pools below, then push out to sea for the castle-on-its-crag silhouette with Ailsa Craig as a backdrop. Sunset is the moment — the whole coast faces west, so you get the sun sinking behind Arran and warm light on the old sandstone. The castle is an open, unstaffed council-owned ruin (not HES or NTS managed), so you can legally take off from the grassy headland beside it under Scotland's access rights. Because it's right on the water the sea breeze can be brisk and gusty around the ruin's walls; keep the drone seaward and mind the rotor turbulence near the stonework. Prestwick Airport's FRZ sits ~13km to the north, so double-check you're outside it before launching (Dunure is comfortably clear). It featured as a filming location for a well-known TV series, so it draws visitors — fly early or midweek and avoid overflying people on the headland.