Cumbe Mayo means “narrow river” in Quechua and it was built by the Caxamarca culture between 50BCE and 200CE, so roughly 2,000 years ago. The Caxamarca pre-dated the Inca by centuries but were eventually conquored by the Inca and co-existed under Inca rule until the Spanish invasion destroyed most of their cultur

It’s a 9km (5.6mi) canal carved into bedrock a standardized 30-45cm wide (12-18in) and 45-60cm deep (18-24in). Along the route there are petroglyphs of simple shapes like stars and crosses, but also zoomorphic shapes like felines and snakes, reminiscent of Moche designs.

At some points the canal is dug through bedrock in a tunnel though most of the time it’s ramrod straight. To control the speed of the water flowing through the canal, in some spots they curved the canal, to speed up the flow, and at other places put in a series of 90 degree angle zig zags to slow the flow.