Other Urban Legendish stories abound, including a Navy engineer examining
battleship plans and noticing a space with no access panels. He eventually
cut through the walls with a torch and found a fully equipped machine
shop -
untouched since the thing was built 20 years before and a cockup in the
plans removed the doors..

There's a railway line in China that is dead straight, except for an
inexplicable curved detour half way between two cities. This is because when
the big cheese was asked for the route for the new line, he took out a ruler
and drew a straight line, except for the bump where his finger protruded
from the straight edge.

I presume this one must be an urban legend, unless someone knows
otherwise...

Christian.