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We present and discuss broad band CCD $UBV(I)_C$ photometry and lowresolution spectroscopy for stars in the region of the open cluster NGC 6996,located in the North America Nebula. The new data allow us to tightly constrainthe basic properties of this object. We revise the cluster size, which in thepast has been significantly underestimated. The width of the Main Sequence ismainly interpreted in terms of differential reddening, and indeed the stars'color excess $E_{B-V}$ ranges from 0.43 to 0.65, implying the presence of asignificant and evenly distributed dust component. We cross-correlate ouroptical photometry with near infrared from 2MASS, and by means of spectralclassification we are able to build up extinction curves for an handful ofbright members. We find that the reddening slope and the total to selectiveabsorption ratio $R_V$ toward NGC 6996 are anomalous. Moreover the reddeningcorrected colors and magnitudes allow us to derive estimates for the clusterdistance and age, which turn out to be $760 \pm 70 pc$ ($V_{0}-M_{V} = 9.4 \pm0.2$) and $\sim 350$ Myr, respectively. Basing on our results, we suggest thatNGC 6996 is located in front of the North America Nebula, and does not seem tohave any apparent relationship with it.Comment: 19 pages, 12 eps figures, in press in A&

Optical photometry and spectral classification in the field of the open cluster NGC 6996 in the North America Nebula