The construction of fully decorated 1,2,3-triazole-fused 5-, 6- and 7-membered rings has been disclosed via a bimetallic relay-catalyzed cascade process combining azide-alkyne cycloaddition, C(sp2)-H functionalization of intermediary 1,2,3-triazoles and isocyanide insertion. The salient features of this methodology include simple starting materials, reduced synthetic steps, good substrate scope and high efficiency.