The annual XTERRA Vashon Island Off-Road Triathlon will take place this Sunday at Dockton Park. The event for serious athletes includes a swim in Puget Sound and a cross-country bike ride and run on Dockton roads and King County parks trails.

New this year, BuDu Racing, the organization that puts on XTERRA, will offer a separate, 3.5-mile fun run in Dockton the same day.

At the fun run, BuDu Racing will offer chip timing, age-group awards, sponsor prizes and post-race food. The race begins at 9 a.m., and runners can register that morning for $17.

For more information or to preregister for $11, see www.buduracing.com; click on the calendar and select Dockton Trail Run.

Participants in the race will be on some roads in Dockton on Saturday morning.