Route 635 is a 35.2-kilometre (21.9 mi) long mostly north–south secondary highway in the southwestern portion of New Brunswick, Canada. Most of the route is in Prince William Parish. The route starts at Route 102 near Kings Landing in where it is known as Prince William Road. It travels west and crosses Route 2 at exit 253. From there, it travels through a sparsely populated area past Lake George, , and Lake George. It intersects with the northern terminus of Route 636 before continuing through Magundy, , Magaguadavic and . It passes Lake Magaguadavic and before ending in at Route 3.