U.S. Route 550 (US 550) is a spur of U.S. Highway 50 that runs from Bernalillo, New Mexico to Montrose, Colorado in the western United States. The section from Silverton to Ouray is frequently called the Million Dollar Highway. It is one of the roads on the Trails of the Ancients Byway, one of the designated New Mexico Scenic Byways. Route description New Mexico U.S. 550 begins just north of Albuquerque at Bernalillo and passes through the towns of San Ysidro, Cuba, Bloomfield, and Aztec. Except for sections passing through the above listed towns, U.S. 550 in New Mexico has been upgraded to four lanes, offering a high-speed (70 mph) connection for Farmington, New Mexico and Durango, Colorado to Albuquerque and Santa Fe. Colorado Most of U.S. 550 in Colorado is two-lane mountainous highway. It is one of only two north–south U.S. Highways in Colorado which runs west of the Continental Divide. (The other route is US 491.) The route travels north through the San Juan Mountains. The Million Dollar Highway stretches for about in western Colorado and follows the route of U.S. 550 between Silverton and Ouray, Colorado. It is part of the San Juan Skyway Scenic Byway. Between Durango and Silverton the Skyway loosely parallels the Durango and Silverton Narrow Gauge Railroad. Though the entire stretch has been called the Million Dollar Highway, it is really the twelve miles (19 km) south of Ouray through the Uncompahgre Gorge to the summit of Red Mountain Pass which gains the highway its name. This stretch through the gorge is challenging and potentially hazardous to drive; it is characterized by steep cliffs, narrow lanes, and a lack of guardrails; the ascent of Red Mountain Pass is marked with a number of hairpin curves used to gain elevation, and again, narrow lanes for traffic—many cut directly into the sides of mountains. During this ascent, the remains of the Idarado Mine are visible. Travel north from Silverton to Ouray allows drivers to hug the inside of curves; travel south from Ouray to Silverton perches drivers on the vertiginous outside edge of the highway. Large RVs travel in both directions, which adds a degree of excitement (or danger) to people in cars. The road is kept open year-round. Summer temperatures can range from highs between at the ends of the highway to in the mountain passes. The snow season starts in October, and snow