I didn't see soccer fields, but most of the athletic fields in the city of Burlington are free to use as long as no one is scheduled to used them. I'm not talking a scheduled practice. But, if you and your kids going to kick a few balls, we never had a problem with the ball fields during the day.
There is professional baseball field. There's a couple softball or basefields and walking track and tennis courts. O. Pretty sure the 2 so get fields across the street belong to someone else
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