Where in Boston?

A tunnel, a castle, a drop-down window, an onion-domed church in suburbia, a train yard.

Answers at the bottom of this post.
















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Answers:

1) Franklin Park. This tunnel runs under the road which runs past the golf course, close to the Forest Hills entrance.
2) This is a former armory which is now the Boston Smith and Wollensky's restaurant, near the Park Plaza hotel
3) ICA (Institute of Contemporary Art: http://www.icaboston.org)
4) Church on South Street, Roslindale. Near Fallon Field
5) Bay State Model Railroad, again in Roslindale.