context: Rocky Mountains () is a vast mountain range in western North America. It stretches 4800 kilometers from Mexico through the United States to Canada. It belongs to the so-called "young corrugated mountains," which have been created over the last 60 million years as collisions of lithospheric tiles. The highest peak of the Rocky Mountains on the US side is Mount Elbert in Colorado. It is 4399 meters tall. In Canada, its highest peak is Mount Robson, which reaches 3,959 meters.
question: How high is the highest peak in the Rockies?
answers.text: 4399 meters