Driving From Monterrey/Saltillo to Zacatecas
 

Does anyone know what the road conditions are on 57 between Monterrey/Saltillo and Zacatecas? My wife and I are from San Antonio and we're thinking about taking a week and driving down there. Is it significatly better or worse than the drive from Monterrey down to San Miguel? I drove to San Miguel about 5 years ago and the conditions were pretty poor. I hear they've improved, though. Thanks