The Western Pichincha Project, a survey and excavation program on the western flank of Ecuador's northern Andes, has so far comprised the discovery of more than 230 archaeological sites and the preliminary subsurface testing of one multi-component site, Nambillo. The Nambillo site is a very long, narrow, ridgetop site in the rainforest. It contains a series of superimposed buried soils, each of which yields cultural remains and which taken together range in age from 1500 BC (radiocarbon years) to the Conquest. The Nambillo site presented particularly difficult conditions for subsurface exploration because of the buried soils and the very dense vegetation. The implementation of a systematic soil-coring strategy and the collection of buried soil samples for phosphate analysis at Nambillo have resulted in a detailed reconstruction of the site stratigraphy, of ancient landforms at the site, and of human activity areas. These reconstructions permit the elaboration of a suitable excavation strategy for future study of the site without recourse to random search tactics of excavation. -- AATA