A couple of route checks on posts above . . .
54/54D goes from Saltillo to Zacatecas
57/57D goes from Saltillo to Matehuala - San Luis Potosi - Queretaro - Mexico City
We also like to meander new routes so understand you do not necessarily want to take the shortest or easiest route.
There is a route truckers take to get to the Colima/Manzanillo coast that avoids Guadalajara if that is your goal. If you have been to Hacienda Contreras by Valle de Juarez/Mazamitla you probably know the route. If not and you want me to try to explain it I can. Many old roads have been rebuilt and are in much better shape so there are roads and routes that are not too difficult to take. The road between Valle de Juarez and Mazamitla has always been very bad and they keep promising to fix it - they were working on it last year but do not know if they have finished or how much they might do. All depends on what you might want to see along the way and what new roads you might want to explore - and how much time you have to wander.
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