499.8 kilometers. Baidu map shows that the distance of Lankang is 499.8km, and the whole journey takes 6 hours 14 minute, passing through Lianhuo Expressway and Shi Tian Expressway. You can also take the D754 train from Lanzhou at Lanzhou Station and get off at Longnan Station. After walking from Longnan Station 170 meters, get on the train station (departure station) and take 17. Walk150m to Longnan Wudu Bus Station sr, then get on the bus at Longnan Wudu Bus Station sr, get off at Yuntai Town, and walk 20m to Kangxian County. The whole journey takes 5 hours and 33 minutes.