Many experienced travelers call Going-to-the-Sun Road, a 52-mile highway that cuts through Montana’s Glacier National Park, the most beautiful road in the world. It was built between 1919 and 1932 at a cost of just over two million dollars, and in 1997 the combination of its panoramic setting and the heroic engineering needed to carve it out of the Continental Divide led to its designation as a National Historic Landmark. Now Going-to-the-Sun Road is starting to show its age. After a six-year renovation proposal provoked grumbling from local businesses, an advisory committee has been formed to search for a compromise. For now, the road continues to carry traffic, though routine maintenance and repair of its guard walls provides some lucky tourists with delays of 15 to 30 minutes in which to pause and take in the scenery.