This supplementary material provides detailed information on the fabrication and failure modes of strong, lightweight, and recoverable three-dimensional ceramic nanolattices. The fabrication process involves creating octet-truss polymer nanolattice scaffolds using two-photon lithography and coating them with alumina using atomic layer deposition (ALD). The structures are then exposed to O₂ plasma to remove the polymer, resulting in free-standing hollow lattice structures. The failure modes of the nanolattices, including fracture, Euler buckling, and local shell buckling, are analyzed using theoretical equations and experimental data. The critical transition values between these failure modes are determined, and the mechanical properties of the ALD alumina are provided. Additionally, the material includes supplementary figures and movies that illustrate the stress-strain behavior, post-compression recovery, and in-situ compression of the nanolattices under different conditions.This supplementary material provides detailed information on the fabrication and failure modes of strong, lightweight, and recoverable three-dimensional ceramic nanolattices. The fabrication process involves creating octet-truss polymer nanolattice scaffolds using two-photon lithography and coating them with alumina using atomic layer deposition (ALD). The structures are then exposed to O₂ plasma to remove the polymer, resulting in free-standing hollow lattice structures. The failure modes of the nanolattices, including fracture, Euler buckling, and local shell buckling, are analyzed using theoretical equations and experimental data. The critical transition values between these failure modes are determined, and the mechanical properties of the ALD alumina are provided. Additionally, the material includes supplementary figures and movies that illustrate the stress-strain behavior, post-compression recovery, and in-situ compression of the nanolattices under different conditions.