where it meets with US 385 at exit 36. The Interstate briefly runs in an east direction through the town of Wildorado before turning back to the southeast. I-40 has a mostly rural route before becoming more suburban in Bushland, with housing developments becoming visible from the highway. The Interstate passes by Cadillac Ranch before the Hope Road interchange and enters the city limits of Amarillo just west of State Highway Loop 335 (Loop 335). I-40 expands from four lanes to six at Loop 335 and runs through a heavily developed area of the city. Near downtown, the highway serves as the northern terminus for I-27 at a turbine interchange and begins an overlap with US 287. I-40 runs through eastern Amarillo, passing by the American Quarter Horse Hall of Fame and The Big Texan Steak Ranch. Development along the route begins to lessen after South Eastern Street as the highway passes near Rick Husband Amarillo International Airport. US 287 leaves I-40 at exit 78 as the Interstate leaves the city limits of Amarillo. The highway runs primarily through rural farmland after leaving the city and enters the town of Groom, passing near a 19-story cross and a leaning water tower. East of Groom, I-40 has an overlap with State Highway 70 (SH 70) between exits 121 and 124. After the overlap with SH 70 ends, the terrain along the Interstate begins to change from flat plains to a rolling canyon ridge with an observation point near Alanreed. I-40 returns to flatland again after the town of McLean and bypasses the town of Shamrock before entering Oklahoma near Texola. Exit list Business routes and old alignments I-40 has seven business routes in Texas, all of which are old alignments of US 66. A number of other old alignments of US 66 are also present; most are marked on guide signs on I-40. Bus. I-40-A (formerly State Highway Spur 504 (Spur 504)) is a business spur that runs from I-40 at Glenrio, just east of the New Mexico state line, southwest to the border. In New Mexico, the road forks—the later paved alignment (c. 1952) has been cut by I-40, and the earlier alignment west to San Jon is now a dirt road that had been paved when it was US 66 prior to 1952, but the paving was later removed by Quay County, New Mexico, commissioners due to high maintenance