This is an LDRaw representation of the actual trestle bridge I built.
It is dual-track, 34x160 studs long (approx. 10"x50") train bridge 
and safely spans 48" while holding two trains.

The parts in pink are mock-ups of some technic pieces I did not have in
my installation of LDRaw, though I'm sure the parts do exist in LDRaw. I
also substituted yellow pieces for constrast while building this in 
LDRaw; these parts really should be light gray.

--Jack
AFOL, GtwLUG, St. Louis