The fourth annual Round the Rock paddle board race is set for Sept. 9 at Seward Park.

The event, which started on Mercer Island, by Islanders, increased in size to the point a bigger location was needed, and moved to Seward Park in their second year.

The 2012 event features the main race, a 13 mile trek around Mercer Island, and will include some of the top racers in the country. Paddlers in the Elite class will be competing for $10,000 in prize money.

A shorter 3.5 mile race, which follows the shoreline of Seward Park will also take place, along with a Kids Race for paddlers ages seven to 14.

There will also be a Team Relay Race, with teams of four competing one mile laps.

The event will begin with a 7 a.m. check in for the 13-mile race, with the race beginning at 9 a.m. The all day SUP expo also begins at 9 a.m., including free demos.

This year proceeds from the event will benefit Stand UP for Kids, a non-profit which works to end homelessness for kids in the U.S.

To learn more about the Round the Rock race, or to register, visit roundtherock.com.