Running northwest of Fairland Regional Park, US 29 reaches its first major freeway segment at Burtonsville, bypassing a former, heavily curved at-grade expressway portion through the community. At this point, it downgrades into a four-lane divided expressway until it enters Howard County. The bypass incorporates the southern end of the former alignment and a diamond interchange with MD 198 within its southern endpoint; US 29 continues straight ahead through the combined interchange, meeting the northern end of the former alignment at a partial diamond interchange. The 0.92-mile bypassed section of the old road is officially designated US 29A with street signs that say "Old Columbia Pike," which previously ended at MD 198.