I-27 is overlapped by US 60 and US 87 from exit 110 north of Canyon to the end of the Interstate in Amarillo; here the frontage roads are one-way. Several near the south end are handled by bridging the intersecting road over all roadways, but, once I-27 crosses Loop 335 (exit 116), almost all interchanges are diamonds. At exit 119A, which marks the south end of the six-lane cross section in Amarillo, Hillside Road passes under both the main lanes and the frontage roads, with two ramps providing partial access. Other connections with Hillside Road are made via Western Street (exit 119B), which crosses the frontage roads at grade. The end of I-27 at Interstate 40 (exit 123B) is a fully directional turbine interchange; U.S. Highway 287 also passes through, using I-40 to the east and US 60/US 87 to the north. Four lanes continue beyond I-40, and are joined by several from the I-40 ramps, making the northernmost portion of the Canyon Expressway five lanes in each direction. Several blocks beyond I-40, the highway ends at a split into two one-way pairs. Northbound traffic feeds onto Fillmore Street (US 87 north) and Buchanan Street (US 60 east and US 287 north), while southbound traffic approaches on Taylor Street (US 287 south) and Pierce Street (US 60 west and US 87 south). The rightmost of the five northbound lanes is barrier-separated from the rest, forcing traffic exiting I-40 west onto Buchanan Street. Through the I-40 interchange and the split, the frontage roads are discontinuous.