ST. PETERSBURG, Fla. -- Earlier this week, we told you about the first-ever 10K across the Sunshine Skyway. Today, we learned it may sell out by Sunday.

Race organizers say the run is 60% sold, and they expect all slots to be gone by Sunday. So if you're interested in running it, you have to act fast!.

The run will be on Sunday, March 4. The bridge will be closed between 4 a.m. and 10 a.m. for the duration of the race.

The 6.2-mile race will start at the rest area on I-275 just south of the bridge and will end at the north side of the bridge.

The event will bus participants back to the start after the race ends. All proceeds raised from the race will go towards supporting the Armed Forces Families Foundation, which supports military families.

“I am thrilled to welcome the inaugural Skyway 10K race to Tampa Bay, and our side of the bridge,” said St. Petersburg Mayor Rick Kriseman. “In particular, I want to thank the organizers of the Skyway 10K for honoring the Armed Forces Families Foundation. Families with loved ones serving in the military deserve our support. I am glad this outstanding race will benefit such a worthy cause.”

Registration opened Wednesday and race entry fees are currently $75.