The Great Union Camera Obscura is a small Victorian oddity on Douglas Head, built in 1892 when Douglas was busy selling itself as a seaside resort. Inside, eleven lenses project moving colour views of the harbour, lighthouse, bay, and cliffs onto a circular table, giving you a slow, analogue panorama before phones made that sort of thing effortless.
It is a weather-dependent attraction and usually opens seasonally, so check the flag or current visitor information before walking up. Even if it is closed, Douglas Head is still worth the climb for the harbour view and the sense of how the old resort town sits between sea traffic and high ground.