How hard is cross-country skiing?

Cross-country skiing - Swedish Tourist Association

Trail Conditions – Cross-Country Skiing

Cross Country Skiing

Beginner's guide to cross-country skiing

Cross-country skiing vs downhill skiing

A primer to help you take the cross-country plunge - New England Ski Journal

Help for Struggling Skate Skiers: Why is it so hard?

After 50 years, 'Birkie Fever' still running hot for northern Wisconsin cross-country ski race

How Difficult is Cross Country Skiing?, snowHeads ski forum

Beginner's Guide to Cross-Country Skiing

Choosing Classic Skiing or Skate Skiing — Cross Country Skiing

Muscle Building for Cross-Country Skiers: Developing Stamina and Leg Power

Cross-country skiing for beginners Learn basic skiing techniques in Norway

Cross-country skiing vs downhill skiing

Beginner's Guide to Cross-Country Skiing