We report the aqueous self-assembly of hierarchical supramolecular polymer-colloidal hydrogels consisting of functionalized polymer-grafted silica nanoparticles, a hydroxyethyl cellulose derivative and cucurbit[8]uril. The resulting material (98 wt% water) can be drawn into uniform (6 μm) ‘supramolecular fibres’ at room temperature. They exhibited better tensile strength and superior stiffness to natural fibres such as viscose, protein-based silks, and human and animal hair, while cyclic loading tests illustrated their remarkable damping capacity (60–70%). These supramolecular hydrogels represent a new class of hybrid supramolecular composites, opening a window into fibre technology through low-energy manufacturing from a broad range of sustainable materials.