Merida's street names

The names of streets in Hispanic cities tend to be of the type of “Avenida 9 de Julio” or “17 de Octubre” or else of the type “Avenida Presidente Luis Saenz Piña” or “Raúl Scalabrini-Ortiz (formerly Canning)” or (fictitious, I'm afraid) “Calle Ingeniere-Marescal Marcantonio-Cesar Ordóñez y Covarrubia-Jiménez.” It's hard to remember such a name, or to know which part in it is actually spoken, or to find it on the map, since it may be one of the north-south or one of the east-west streets. You are told that a place is “at Bustamante and Charcas” or “on Córdoba between Peru and Juncal y Oro.” And names get changed at the accession or apotheosis of a politician: while we were in Buenos Aires, signs on part of the Avenida de Mayo were over-stuck with labels for the recently deceased president “Nestor Kirchner.”
        Mérida, however, is different. We're talking about the Mérida in Mexico, not the original Mérida in Spain (founded in 29 BC as a settlement of the emeriti or retired soldiers of the emperor Augustus's army). Mexican Mérida was founded by the Spanish in 1574 on the site of a much older Mayan city, and it is the capital of the large flat province of Yucatán.

        Its street plan is a grid, in which north-south streets have even numbers and east-west streets odd numbers. So directions are given in the form “It's on 69 between 64 and 66,” or, as written for you by someone on a scrap of paper, “69 x 64 y 66.” This looks remarkably like an expression in Cartesian rectangular coordinates, where “x” means the left-right dimension, “y” the front-to-back dimension, and “z” the up-and-down dimension. However, in Meridan geometry “x” means “between” and “y” means “and.” The system is rational, but not easy, without the inhabitants' long practice, to keep clear in the head: since the city is about sixty blocks across in both directions, all streets of both directions in the middle have numbers in the sixties.
        Mérida is a lively town. The central plaza is usually full of crowds and loud music; at night the streets nearest to the plaza are cordoned off for the multitude of pedestrians. You can find this central plaza between 60 and 62 and between 61 and 63.