cross-country skiing

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun The sport of skiing over the countryside rather than on downhill runs.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun An endurance sport and method of getting about involving travelling on skis, uphill as well as downhill .
• noun A leisure activity using cross-country skis and ski poles for traversing natural terrain during winter.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun the sport of skiing across the countryside (rather than downhill)