  We have developed a maximum-likelihood procedure to fit theoretical
isochrones to the observed cluster color-magnitude diagrams of NGC 6866, an
open cluster in the Kepler Spacecraft field of view. The Markov-Chain Monte
Carlo algorithm permits exploration of the entire parameter space of a set of
isochrones to find both the best solution and the statistical uncertainties.
For clusters in the age range of NGC 6866, with few if any red giant members, a
purely photometric determination of the cluster properties is not
well-constrained. Nevertheless, based on our UBVRI photometry alone, we have
derived the distance, reddening, age and metallicity of the cluster and
established estimates for the binary nature and membership probability of
individual stars. We derive the following values for the cluster properties:
$(m-M)_V = 10.98\pm 0.24$, $E(B-V) = 0.16\pm 0.04$ (so the distance = 1250 pc),
age $= 705\pm170$\ Myr and $Z = 0.014\pm 0.005$.
