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Nitrogen adsorption studies have been employed to examine the structural properties of micro-/meso-porous carbons obtained by colloidal templating and post-synthesis KOH activation. These carbons were prepared by polymerizing phenol and formaldehyde in the pores of a colloidal silica template followed by carbonization, silica dissolution and post-synthesis KOH activation. Colloidal silica was used to create spherical mesopores, while KOH activation was performed to create additional microporosity and to enlarge the surface area of the resulting carbons. Nitrogen adsorption studies showed that a single impregnation of the colloidal silica template with phenolic resin precursors afforded carbons with relatively thin pore walls which did not withstand the post-synthesis KOH activation; however, a double impregnation generated mesoporous carbons with thicker pore walls. Activation of these latter carbons with KOH created micropores in the mesopore walls without significant deterioration of the mesopore structure. The resulting mesoporous carbons possessed high specific surface areas (ca. 800 m2/g) and large single-point pore volumes (ca. 1.8 cm3/g). The post-synthesis KOH activation enlarged the surface area up to 1500 m2/g, which was achieved via the creation of microporosity. Hence, the carbon obtained by double impregnation and activation exhibited a single-point pore volume of ca. 2 cm3/g with a relatively high microporosity which attained 17% of the total porosity. High-surface-area micro-/meso-porous carbons are attractive for adsorption, catalysis and energy-related applications such as capacitors and batteries. [ABSTRACT FROM AUTHOR]