See main section. If you are coming from the Quito side, you just begin climbing on the first ridge encountered.
Under "Time Required", a "long day" means from Quito. The actual rock scramble is pretty short.
***Note: the summit is actually around 4710 meters high*** If you have some rock climbing experience and you are like me and don't like to climb arenal (arena=sand, arenal=steep bank of soft sand that makes climbing tedious) then this is the route to take. Just start climbing the ridge that the east-side trails lead up to and follow the ridge line until you reach the summit. Notable exposed areas are the beginning section, where the ridge is narrow and a short bit of low 4th class is encountered, and the short knife-edge saddle known as "El Paso del Muerte", where a single low fifth-class move pulls you up onto the rocky little pass shortly before the summit.
The arenal is very nice for the descent, so after summitting, scramble straight down the steep northern face (climber's right) until you hit sand, and then plunge-step your way down to the traverse trail, at which you head to the right to get back to Quito.
You can do this in hiking boots without any climbing equipment, as long as you trust your grip.
If you have information about this route that doesn't pertain to any of the other sections, please add it here.