BALTIMORE (WJZ)—It’s a unique opportunity to do something in Baltimore you’ve probably never done before, and at the same time you can help others.

Ron Matz reports Sunday is your chance to take a run or walk through the Fort McHenry Tunnel.

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It’s year five for the Fort McHenry Tunnel Run and Walk. Three tubes will remain open to traffic, but one will be reserved for runners.

It’s a benefit for Special Olympics Maryland.

“This is the fifth annual. It’s gotten bigger every year. We had over 900 runners last year. This year we’re shooting for over a thousand,” said Jim Schmutz, president of Special Olympics Maryland.

The Maryland Transportation Authority Police make it happen.

“I’m very excited. I never ran through a tunnel, so I know that when we do our cadence as we’re running, it’s going to sound very good,” said Frederick Delaney II, MDTA police recruit class 46.

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Special Olympian Annu Singleton made the run last year in an event that continues to grow.

“I’m ready for the run. I did it last year. I enjoyed it so much I’m doing it again this year. I will give it my all,” Singleton said.

“It’s a huge deal. It’s a year round planning effort of the MDTA. We have a 20 person committee. We raised $50,000 last year to support our athletes,” Schmutz said.

All 34 members of the MDTA recruit class will be making the tunnel run.

“It’s an honor to be able to take part in this event. It’s for a good cause. I have family members who have special needs, so I definitely understand the needs,” said Leory Posey, recruit class 46 MDTA Police.

It’s fun on your feet, under the harbor.

“It’s a bucket list for some folks. It’s the only time during the course of the year from a pedestrian standpoint that you can get into the tunnel. It’s a great opportunity,” Schmutz said.

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There’s still time to register for the Fort McHenry Tunnel Run and Walk. It’s $30 pre-registration and $35 on race day. For more information, just click here.