The highway widens to four lanes with a turn lane shortly after crossing into Renesslaer County, and will remain so for most of the rest of the way to Albany, despite limited development and low traffic in some areas. Within a mile of the county line it passes under the New York State Thruway Berkshire Connector and meets the lone section of I-90 in New York not part of the Thruway system, at exit 12 southeast of Castleton-on-Hudson. north of I-90 and northwest of Nassau, US 9 veers left to merge with US 20 in Schodack Center, and together they progress northwest toward Albany. Less than from the eastern terminus of the overlap, US 9 and US 20 intersect NY 150 before connecting to I-90 at exit 11.