Atomic force microscopy (AFM) of microfibres fabricated from the self-assembly and fracturing of silica nanoparticles reveals mesoporous structure with hcp packing. Pore size distribution for (20 – 30) nm sized particles are calculated to lie within rtet ~(2.2 – 3.3) nm and roct ~(4.2 – 6.2) nm for the octahedral and tetrahedral sites. The experimentally measured distribution, using N2 adsorption, is r ~(2 - 6) nm, in excellent agreement suggesting a highly controllable and periodic porosity using these structures. The potential for a number of material and device applications is discussed.