  Cam OB3 is the only defined OB association believed to belong to the Outer
Galactic Arm or Cygnus Arm. Very few members have been observed and the
distance modulus to the association is not well known. We attempt a more
complete description of the population of Cam OB3 and a better determination of
its distance modulus. We present uvby photometry of the area surrounding the
O-type stars BD +56 864 and LS I +57 138, finding a clear sequence of
early-type stars that define an uncatalogued open cluster, which we call
Alicante 1. We also present spectroscopy of stars in this cluster and the
surrounding association. From the spectral types for 18 very likely members of
the association and UBV photometry found in the literature, we derive
individual reddenings, finding a extinction law close to standard and an
average distance modulus DM=13.0+-0.4. This value is in excellent agreement
with the distance modulus to the new cluster Alicante 1 found by fitting the
photometric sequence to the ZAMS. In spite of the presence of several O-type
stars, Alicante 1 is a very sparsely populated open cluster, with an almost
total absence of early B-type stars. Our results definitely confirm Cam OB3 to
be located on the Cygnus Arm and identify the first open cluster known to
belong to the association.
