Here is a guess: Ehrenbreitenstein on the right bank of the Rhein opposite Koblenz. The height looks right and the church on the left bank with the 2 towers in the enlargement appears to be a gothic structure with the single tower church sort of a Zweibelturm looking thing. Railroad would have crossed Rhein at Koblenz. Note artist's name is abreviiated so it is only an assumption that it is William. The middle initial appears to be a W not an M.
Anyway, Ehrenbreitenstein was a world famous fortress from just after the Napoleanic period and hence would have been a popular subject for amateur painters in the 2d half of the 19th century. The fortress remains today and can be visited.
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