BALTIMORE (AP) — Registration is underway for an annual charity race that givers runners the chance to race under Baltimore’s harbor.

The Maryland Transportation Authority says runners can now register for the sixth annual Fort McHenry Tunnel 5k run and walk. The run uses the northbound right tunnel tube of the Fort McHenry Tunnel as part of the race course.

The race will take place Sunday and benefits Special Olympics Maryland.

The entry fee is $30 during pre-registration and $35 on race day. The 2013 event raised more than $40,000.

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