We propose here a two-dimensional material based on a single layer of violet or Hittorf’s phosphorus. Using first-principles density functional theory, we find it to be energetically very stable, comparable to other previously proposed single-layered phosphorus structures. It requires only a small energetic cost of approximately 0.04 eV/atom to be created from its bulk structure, Hittorf’s phosphorus, or a binding energy of 0.3 − 0.4 J/m^2 per layer, suggesting the possibility of exfoliation in experiments. We find single-layered Hittorf’s phosphorus to be a wide band gap semiconductor with a direct band gap of approximately 2.5 eV and our calculations show it is expected to have a high and highly anisotropic hole mobility with an upper bound lying between 3000−7000 cm^2V^−1 s^ −1 . These combined properties make single-layered Hittorf’s phosphorus a very good candidate for future applications in a wide variety of technologies, in particular for high frequency electronics, and optoelectronic devices operating in the low wavelength blue color range.