  Subaru observations of A1689 (z=0.183) are used to derive an accurate,
model-independent mass profile for the entire cluster, r<2 Mpc/h, by combining
magnification bias and distortion measurements. The projected mass profile
steepens quickly with increasing radius, falling away to zero at r~1.0 Mpc/h,
well short of the anticipated virial radius. Our profile accurately matches
onto the inner profile, r<200 kpc/h, derived from deep HST/ACS images. The
combined ACS and Subaru information is well fitted by an NFW profile with
virial mass, (1.93 \pm 0.20)10^15 M_sun, and surprisingly high concentration,
c_vir=13.7^{+1.4}_{-1.1}, significantly larger than theoretically expected
(c_vir~4), corresponding to a relatively steep overall profile. A slightly
better fit is achieved with a steep power-law model that has its 2D logarithmic
slope -3 and core radius theta_c~1.7' (r_c~210 kpc/h), whereas an isothermal
profile is strongly rejected. These results are based on a reliable sample of
background galaxies selected to be redder than the cluster E/S0 sequence. By
including the faint blue galaxy population a much smaller distortion signal is
found, demonstrating that blue cluster members significantly dilute the true
signal for r~400 kpc/h. This contamination is likely to affect most weak
lensing results to date.
