During Cretaceous times, the Colombian Andes underwent major geological changes. In the Colombian East, which is located east of the Otú-Pericos fault, distension and subsidence brought about the formation of a large basin in which thick sequences of epicontinental sediments were deposited. In the Colombian West, an oceanic domain with ophiolites was generated in an allochthonous position and later thrust over the continental margin. This first tectonic event is associated with a mid to high pressure metamorphic event. Later an island-arc magmatism developed, characterized by the formation of volcanic-sedimentary assemblages and an intermediate plutonic belt. A second important tectono-metamorphic event affected the entire Colombian West during Late Cretaceous times, and a later magmatism of intermediate composition marks the termination of the tectono-genesis. The assemblage between the Colombian East and the Colombian West occurred during the end of the Cretaceous or beginning of the Cenozoic, with large-scale lateral displacement along the Otú-Pericos fault. This movement continued later along the Cauca-Romeral system that crosses the tectono-metamorphic structures formerly created. A comparison between the Colombian and Ecuadorian Andes shows similarities with regard to the lithostratigraphy of several terranes, both oceanic and continental, and with regard to several accretion ages. However, the distension and subsidence that affected the Colombian East seem to be features exclusive to the northern region.