Yucundaa is the hilltop Mixtec settlement that came before colonial Teposcolula. The site was abandoned after the Spanish founded the new town around the Dominican convent, but its platforms and traces of occupation still give the valley a longer memory.
It is a more demanding stop than the central sights, partly because information on the ground can be thin. Go for the landscape and the context: from here, the convent in town reads less like an isolated monument and more like the start of a forced reordering of the Mixteca.