Guanajuato is famous for its network of tunnels that were built in 1956 to help keep the traffic problems under the center of town.
The first tunnel was built on the old river bed that was left after they detoured the river. There are enough tunnels that they have to have street names at entrances and also at junctions inside the tunnels
Not a lot of lite is used in the tunnels we came to some areas where there was parking and stairs to reach the city above.
In the old part of town there are not many roads that two vehicles can drive down at the same time