Scolpaig Tower is a small octagonal Georgian folly built around 1830 on an islet in Loch Scolpaig, on North Uist. It replaced an older broch, which was not the best bargain history ever made, but the tower still cuts a memorable shape against the loch and low moorland.
You can reach the islet at low tide, though most visitors are content to view it from the shore. The interior is derelict, so treat it as a landscape sight and photo stop rather than a building to explore.