Ultra-Running Resource Site — Gives you information on every aspect of ultra-running.

Official Website of the Western States 100 — A great site to look at to understand what's involved in an endurance run.

American Ultra-Running Association — A resource for news and information on ultra-running in the United States.

Ultrarunning Online — Provides interesting articles and photos for ultra-runners.

What Is an Ultramarathon Walk? — When that point in time arrives that a walking marathon just isn't long enough.