sentences:  During the 1990s and early 2000s, the NCDOT invested more than one hundred million dollars upgrading U.S. 64, U.S. 421 and U.S. 15–501, which had previously been two-lane roads, to multi-lane highways.There is now a U.S. 64 bypass north of Pittsboro; a similar freeway diverts traffic on U.S. 421 east of Siler City.Chatham County is served by two public transit providers – Chatham Transit Network and Chapel Hill Transit.