Mamma Mia! filmed at Agios Ioannis Kastri, Skopelos. The tiny chapel on a rock stack reached by about 200 steps; the wedding scene. On screen it's The chapel on the rock.
Probable Named in published production coverage; the coordinate is the place itself, checked against a gazetteer.
Venture keeps every scene location on one map, sorted by how far you'd have to walk. Open it in Skopelos and it tells you what was shot around you, how to get there, and whether you can actually go in.
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