Ajusco from Afar

I continually mention that I went mountain biking at Ajusco this weekend or that weekend. But what exactly is Ajusco. Ajusco is the tallest mountain in a mountain range to the southwest of Mexico City. I drive about half way up Ajusco to a park called San Nicolas (or as the locals call it, las llantas, which means tires. The parking area has a lot of car tires used to terrace the hill side). On clear sunny days, like today, I get a good view of Ajusco from my roof deck.