[ http://en.wikipedia.org/wiki/18MEX ]

18MEX is a railroad operations and share trading board game in the 18XX
series, published by Deep Thought Games, LLC in 2005. The game was
designed by Mark Derrick and is set in Mexico. It features a government
railroad that optionally absorbs only one company (with additional limits
on which companies may merge into it), so it can be dangerous to plan on
being able to get rid of a trainless company through merger. Like most of
Mark's games, dot-towns don't count against trains so part of the strategy
is arranging to pick up as many of them as possible while still getting
through important cities. In addition, there are three minor companies
which operate under restricted rules in the early game.

[ http://en.wikipedia.org/wiki/18MEX ]