ST. PETERSBURG, Fla. (AP) — For the first time ever, the Sunshine Skyway bridge will shut down to for a road race.

Up to 7,000 racers are expected to tackle the span from 4-10 a.m. on March 4.

The race , called the "Skyway 10k Saluting Military Families," was announced Wednesday by the Armed Forces Families Foundation. Only the northbound lanes will be closed.

The group has agreed to reimburse the state for all lost tolls, and expects to raise a half-million dollars for military families.

About 4,000 vehicles use the northbound lanes of the bridge on a typical Sunday at that time of year and during those morning hours.

The race is a challenge for participants because the bridge is steep and reaches 197 feet (60 meters) high. It spans Tampa Bay between Pinellas and Manatee Counties.