Techniques for producing a glass structure having interconnected macroscopic pores, including providing a polymeric structure having interconnected macroscopic pores; providing polymerizable glass precursors; filling pores in the polymeric structure with the polymerizable glass precursors; polymerizing the polymerizable glass precursors to yield a filled polymeric structure; and decomposing the filled polymeric structure to produce a glass structure having interconnected macroscopic pores. Techniques for filling pores of such glass structure with a material having a high refractive index, and for then removing the glass structure. Structures can be produced having interconnected macroscopic pores and high refractive index contrasts, which can be used, for example, as photonic band gaps.