Two new hexadecanuclear lanthanide complexes employing the 1,5-bis(salicylidene)carbohydrazide (H2bsc) ligand are reported herein. These polynuclear aggregates crystallize in the R3[combining macron] space group, which is unprecedented in a family of lanthanide complexes with such high nuclearity. Magnetic susceptibility measurements reveal weak intramolecular interactions between the magnetic centres, and in the case of compound 2 (DyIII), single-molecule magnet properties are observed.