On both sides of the border, large areas of the mountains are designated national parks (the Krkonoše National Park in the Czech Republic and the Karkonosze National Park in Poland), and these together constitute a cross-border biosphere reserve under the UNESCO Man and the Biosphere Programme. The source of the River Elbe is within the Krkonoše. The range has a number of major ski resorts, and is a popular destination for tourists engaging in downhill and cross-country skiing, hiking, cycling and other activities.