We examined the influence of memristor geometry on switching endurance by comparing ribbed and planar TiO(2)-based cross-point devices with 50 nm × 50 nm lateral dimensions. We observed that planar devices exhibited a factor of over four improvement in median endurance value over ribbed structures for otherwise identical structures. Our simulations indicated that the corners in the upper wires of the ribbed devices experienced higher current density and more heating during device forming and switching, and hence a shorter life time.