  We give a determination of the phenomenological value of the Wilson (or
gradient) flow scales t0 and w0 for 2+1 flavours of dynamical quarks. The
simulations are performed keeping the average quark mass constant, which allows
the approach to the physical point to be made in a controlled manner. O(a)
improved clover fermions are used and together with four lattice spacings this
allows the continuum extrapolation to be taken.
