This extended loop ride goes east from Oaxaca city out through the Tlacolula Valley; then runs south across the ridgeline into the Zimatlan Valley at Guegorexe, not many miles north of Ocotlan; then returns to the capital via highway 175. At 46.1 miles (74.2 km), it is a full day’s ride. The elevation gain & loss is 2520 feet (768 meters). The outing is 7 miles less if you begin and end in the Zocalo in downtown Oaxaca, and skip the part from & to San Felipe. Most of the ride takes place on bike paths and dirt roads; but the section from near Guegorexe back to Oaxaca city is on the shoulder of a busy highway. The ride is rated “Moderate to Difficult” primarily because of the distance. The grades are not too demanding, and there are no technical aspects on the route.
The batteries in my GPS died about the time I got to highway 175, so the track and mileage shown from that point on is an approximation. However, as you are riding along the highway and there is good signage, you cannot get lost.