  We present new B, V and I-band photometry for a sample of 43 local subdwarfs
with HIPPARCOS parallax errors < 13%, in the metallicity range -1.0 < [Fe/H] <
-0.3, which we use to perform main sequence (MS) fitting to the Galactic
globular cluster 47 Tuc. This sample is many times larger than those used in
previous MS-fitting studies and also enables us to fit in two colour planes,
V/(B-V) and V/(V-I). With this enlarged subdwarf sample we investigate whether
the current discrepancy in empirical distance estimates for 47 Tuc, arising
from recent MS-fitting and white dwarf fitting results, is due to inaccuracies
in the MS-fitting method. Comparison of published photometries for 47 Tuc has
revealed systematic offsets which mean that the $(B-V)$ main-line used in
previous studies may be too blue by ~ 0.02 mag. We have derived main-lines in
V/(B-V) and V/(V-I) from the data of Kaluzny et al. (1998), which we have
recalibrated from the `secondary' standards in 47 Tuc of Stetson (2000). Using
an assumed cluster reddening of E(B-V)=0.04, our best-fit apparent distance
modulus is (m-M)V=13.37 (+0.10)(-0.11) in both colour planes, which implies a
cluster age of 11.0 +/-1.4 Gyr and leads to a dereddened distance modulus of
(m-M)0=13.25 (+0.06)(-0.07). Comparison with previous work shows that our
apparent distance modulus is ~0.2 mag smaller than those derived in previous
MS-fitting studies. The difference is accounted for by our preferred cluster
reddening and the recalibration of the cluster photometry, which has made the
main-line redder by an average of 0.02 mag in (B-V). Independent support for
our MS-fitting distance comes from consideration of the Red Clump in the
cluster, from which we derive a dereddened distance modulus of (m-M)0=13.31
+/-0.05, which is in agreement with the MS-fitting result. (Abridged)
