If Mamamag is the top of the climb, Santa Martha is the other end of the story: the foothills where the Andes tip into the coastal plain, thirty-odd kilometres from Naranjal and a long way from anywhere that feels like highland. The air is thicker and wetter here, and the vegetation changes from tussock grass to ferns, bamboo and the dense green of the western slopes.
This is another piece of the old Inca highway, the Qhapaq Ñan, which linked the high settlements around present Cuenca with the lowlands, where cacao, cotton and other goods were traded up the mountains. The Cañari and the Incas before the Spaniards moved loads on foot and on llama trains, which explains the stone paving and the careful drainage on the steepest sections.
On a motorcycle, the descent from Cajas towards Naranjal is one of the most dramatic changes of climate you can ride in a single morning. Corners come in long series, the cloud forest closes in and then drops away, and the temperature climbs so quickly you will want to stop and peel off the layers you put on at the top. Damp surfaces and landslide debris are real hazards, particularly in the rainy season from about December to April, when sections of the road can be closed or reduced to one lane. Trucks heading for the port at Guayaquil use the road, so overtaking calls for patience on the tight bends.
Naranjal is a banana and cacao town of about thirty thousand people and is the place to refuel, eat rice and fish at a simple place near the market, and get out of the heat. Ecuador's coastal lowlands are among the world's biggest banana exporters, and you will pass plantation after plantation with the fruit bagged in blue plastic. Come in the drier months for the better visibility on the mountain section, and start early, because afternoon cloud sits low over the pass and the lowlands bring thunderstorms in the heat of the day. Water is available in every village, but carry your own bottle for the climb.