County Route 105 (Suffolk County, New York)

County Route 105
Cross River Drive
Map of Suffolk County on Long Island with CR 105 highlighted in red
Route information
Maintained by SCDPW
Length:	5.30 mi (8.53 km)
Existed:	1973 – present
Major junctions
South end:	CR 104 in Flanders
	NY 24 in Flanders NY 25 in Aquebogue
North end:	Sound Avenue in Northville
Highway system
County Routes in New York County Routes in Suffolk County ← CR 104 CR 106 →

County Route 105 (CR 105) is a major north–south county road in Suffolk County, New York, in the United States. It is a four-lane, mostly divided highway that runs from CR 104 to Sound Avenue in Northville, west of the western terminus of CR 48 in Mattituck.

The road begins at an at-grade interchange with CR 104 in the David Allen Sarnoff Pine Barrens Preservation Area, southwest of Flanders. It immediately curves from an east–west trajectory to a north–south one before its intersection with New York State Route 24 (NY 24). From that point on, the road becomes a semi-limited-access highway as it crosses the Peconic River before running through Riverhead Golf Course and crossing Sawmill Creek. A diamond interchange exists for a park road in Indian Island County Park, followed by a quarter-cloverleaf interchange for Hubbard Avenue near the Main Line of the Long Island Rail Road.

North of NY 25 in Aquebogue, a cloverleaf interchange was planned for the formerly proposed Long Island Expressway Extension. CR 105 replaces Union Avenue south of the intersection with CR 43 (Northville Tunrpike) in Northville, only to run along the west side of the former Riverhead Air Park, and finally terminates at Sound Avenue.