Runners registering for the 35th Grandma's Marathon field have until Thursday to enter the race at a reduced cost.

Beginning April 1, the current entry fee of $90 increases to $100. The race will accept entries for the annual Two Harbors-to-Duluth event through June 1, or until the 10,000-runner limit is reached – more than 6,900 have entered thus far.

Registration for the June 18 race is available exclusively online at www.GrandmasMarathon.com.

"This was the first time we utilized a true tiered pricing structure for marathon registration and we are very pleased with how well it has worked. We are well ahead of where we were a year ago and we are looking forward to our 35th marathon celebration," said Scott Keenan, executive director of Grandma's Marathon.

Among the festivities planned for the milestone event is a reunion for the North Shore Striders -- the Twin Ports' running club which hosted the inaugural race in 1977. Also, all marathon participants will receive a commemorative Grandma's Marathon cinch bag and an aluminum water bottle.

The 35th Grandma's Marathon weekend also features the Garry Bjorklund Half Marathon and the William A. Irvin 5K. While registration for the Garry Bjorklund Half Marathon is closed, the William A. Irvin 5K has about 200 spots remaining for the June 17 race.

For more information on any of Grandma's Marathon's races or events, visit www.GrandmasMarathon.com.

2011 Grandma's Marathon Online Registration Schedule

Grandma's Marathon (Limited to the first 10,000 entrants) -- Registration Open Through June 1

Garry Bjorklund Half Marathon (5,700 entrants selected via lottery) -- Registration Closed

William A. Irvin 5K (Limited to the first 1,700 entrants) -- Registration Open, 200 spots remain

Source: Grandma's Marathon press release