100 km road races

North American Races

Canada
• Prairie Inn Harriers Elk/Beaver Ultras - Victoria, B.C (5/2/2009)
• ACU National Championships - Toronto, Ontario (5/1/2010) - Cancelled for 2009

USA
• Iron Horse 100k - Orange Park, FL - 2/21/2009
• Dizzy Daze 100k/50k - Seattle, WA - 3/28/2009
• Ruth Anderson 100km - San Francisco, California (4/18/2009)
• WSU 100k relay and solo - Washington State University, Pulman, WA (4/19/2009)
• Lake Waramaug - New Preston, Connecticut (4/26/2009)
• Pony Express - Cameron Park, California (2/28/2009) - If you run fast sub-11 hours, he'll let you run a 100k.
• Green Lakes 100k - Fayetteville, New Your (8/30/2009)

Asian and Australian Races

Japan
• 2002 Ultramarathon Calendar Dated, Also mentions races at other distances.

Australia
• Gold Coast 100 - Gold Coast, Queensland (6/7/2009)

European Races

Belgium
• Night of Flanders 6/19/2009 - World Cup and WMA (masters) championships

Netherlands
• Stichting Ultraloop Winschoten - Winschoten, NL (9/12/2009)

Italy
• del Passatore - May 30-31, 2009
• San Giovanni Lupatoto or results? - September 26 - 27, 2009. It looks like this may be a 24 hour race and limited to Italians.

Spain
• Santander - September 26, 2009

Calendars

International
• ACU International Calendar
• Ultramarathon for you
• Run The Planet
• ultrafondus
• Longest Running Ultramarathons 22

Canadian
• ACU Canadian Championship Calendar

Italian
• calendari

United States
• Southern California Ultra Series

Organizations

• International Association of Ultrarunners
• USA Track and Field
• USATF - Southern California Association
• USATF - Pacific Association
• American Ultrarunning Association
• Association of Canadian Ultramarathoners (ACU)
• Italian Ultrarunning and Trail Association
• Association of Road Running Statisticians

Records, Standards, and Other Lists

• All-Time 100 km Road

Other Websites

• Stan Jensens Run 100s website - If you had to pick one website for ultra running information, this would be it.