Most travelers first glimpse the Catskills from the New York State Thruway, which links New York City and Albany. About 10 mi west of the thruway the mountains rise abruptly from the valley floor in an uneven blue wall some 20 mi long. In the northern Catskills, the Hudson River towns of Kingston and Catskill (thruway exits 19 and 21) are jumping-off points for Routes 23, 23A, and 28, which climb the mountainous wall and snake through Greene and upper Ulster counties. The principal access routes through Delaware County, which lies to the west of the mountains separating the Hudson and Delaware river watersheds, are Routes 23, 28, and 30. Sullivan County and the Upper Delaware River region can most easily be accessed via Route 17 (at this writing morphing into I-86), which runs from the thruway westward through the Catskills.
Numbers in the text correspond to numbers in the margin and on The Catskills map.