A region streching from the Bronx to Albany. It includes the immediate suburbs of NYC (Westchester, Rockland), the NYC exurbs (Orange, Putnam, Dutchess), and the upper hudson valley (Idont remember the counties). Generally a mix of suburbs and exurbs, but once you get past Poughkeepsie its all farm land. Considered upstate to city people.
oh, and by the way, monticello is not part of the hudson valley.
The Hudson Valley is vast.