Hanover — Organizers of the Children’s Hospital at Dartmouth’s annual “HERO” race warn that roads in Hanover and Norwich will see closings and delays on Sunday.

The CHaD HERO event, for which organizers are expecting roughly 4,000 participants, helps raise funds to support the children’s hospital, as well as more than 15 other locations in New Hampshire and Vermont. Many participants wear superhero costumes to match the event theme.

Organizers expect as many as 4,000 runners, walkers and bikers in the day’s races, which will include a half marathon through Hanover and Norwich, a 5,000-meter run and walk, a 10,000-meter wooded hike, a 50-mile bike ride and a one-mile fun run through Hanover. The races will start at 11:15 and noon, according to a news release from CHaD, and racers will be on the course until 3 p.m.

The release told Norwich residents to expect delays around lunchtime on Main Street, Beaver Meadow Road, Moore Lane, Turnpike Road, Church Street and West Church Street, and River Road. An accompanying map showed a planned detour using River Road around the section of Route 5 leading into downtown.

Closings and detours are more extensive in Hanover, with numerous roads remaining inaccessible to traffic between 11 a.m. and 3 p.m. East Wheelock Street also will be closed nearly the entire day — from 4 a.m. to 6 p.m. — between Main Street and Park Street.

— Staff report