More Fun, Less Guilt.(Brief Article)

Ecotourism in Mexico is slow getting off the ground. But the promise is there.

South of Mexico City, where the old two-lane to Cuernavaca makes a slow shift from bustling to deserted, is one of the more ruggedly beautiful landscapes in North America: the Ajusco Mountains. Black lava cliffs give way to lush forests that are home to, among other species, the Zacatuche rabbit that lives only in these volcanic hills. Because of the forests' importance in supplying Mexico City with water, the federal government has named the area a protected green belt.

There is, by Mexico standards, another amazing sight in the Ajuscos: cyclists, hundreds of whom come each day to …