In traveling to the Basilica de Guadalupe the police stopped us because our brand new rental car was polluting. In fact there was no visible exhaust - but for several dollars US we could avoid arrest. We feigned ignorance of the language and were able to convince the police to lead us to the rental agency where we parted with the car - and gave to police 2 dollars for their help. We then used the subway to visit the Basilica de Guadalupe, the richest and most visited Catholic shrine in all the Americas. It is a complex set of buildings where legend has it that in 1531 a brown skinned Virgin Mary miraculously appeared to the Indian Juan Diego.