The MS Harborfest’s 31st annual Regatta is underway in Portland Harbor.

The sail boat race was delayed for about an hour until the wind came up. About 50 boats are taking part in the race, one of many events in the three-day festival that raises money for multiple sclerosis.

The boats race to a buoy off Portland Head Light and then return.

The festival started with an auction Friday and will conclude Sunday with a 5-kilometer run at 9 a.m. at Fort Allen Park, and lobster boat races and a tug musters in the harbor starting at 10 a.m.