The Main Street Half Marathon & 4 Miler is an annual October race in Hunterdon County, New Jersey, offering a half marathon and a 4-mile run. The half marathon begins at the Red Mill Museum in Clinton, and the 4 Miler starts on Kiceniuk Road in Annandale. Participants for both races receive bus transport from Hunterdon Medical Center to their respective start lines. A walkers-only start is available for the half marathon, making the longer distance accessible for those who wish to complete the full course without running.
The course follows Hunterdon County country roads, with organizers as crossing a river, woods, and passing at least one private residence. The event concludes with a gathering at Hunterdon Healthcare in Flemington, with proceeds benefiting the Hunterdon Regional Cancer Center. Both distances include a T-shirt. The event cultivates a local atmosphere while providing organized race-day services, such as packet pickup the day prior, shuttle buses, staggered starts, and a communal finish celebration.