Travelers who plan to take “the back roads” to Las Vegas in March, take note: several roads will be closed to all traffic between noon and 10 p.m. between through March 18 while Union Pacific upgrades the railroad tracks. The Kelbaker Road crossing at Kelso will be closed March 4. Drivers should use I-15 or US Route 95 instead. The Cima Road crossing at Cima will be closed March 6, 7 and 8; use Kelbaker Road to drive between I-40 and I-15. And the Ivanpah Road crossing, nine miles south of Nipton Road, will be closed March 17 and 18.