On the opposite riverbank, I-81 initially runs past a line of lakefront houses and cottages; however, it soon enters a large marshy area named Big Bay Swamp. The wetlands reach as far north as Central Square, a village just west of I-81's interchange with NY 49. For most of the next , I-81 runs north across a mixture of swamps and fields, both undeveloped and fairly level in elevation. Along this stretch, the freeway links to two more major routes: NY 69 and NY 104. The highway eventually reaches the village of Pulaski, where it reconnects to NY 13 at a partial interchange east of the village center. From here to Watertown, I-81 loosely parallels Lake Ontario, located about to the west and more closely followed by NY 3. Another substantial stretch of open, rolling fields brings the route to Sandy Creek, where it connects to County Route 15 (CR 15), a highway designated NY 288 during the 1930s.