There were plans for a simple tunnel portal in the Feb 2005 issue of Garden Railways, by Steve Haskew.
Crimson Star
http://www.crimsonstar.com/rr
Visit http://spjrr.com/sp/ (Smith Pond Junction RR Products). They tunnel portal plans and kits.
Does anyone have plans for a wooden tunnel portal? I need to make/acquire 2 for an upcoming show.
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