The Third Annual Urban Ag Fair is being held on the site of Newtowne’s first marketplace in the 1630s – the corner of Mt. Auburn & JFK Streets, Harvard Square, Cambridge,  and will showcase some incredible locally grown fruits and vegetables. Visitors can sample recipes prepared using local ingredients and get tips from local experts on gardening topics like composting, container gardening, and raising chickens and bees. The entire event is free, open to the public, and family-friendly. Cooking demonstrations by local chefs and Cambridge School student growers will be held throughout the day, along with talks on gardening topics. Prizes will be awarded for fruits, vegetables, flowers, honey, eggs, baked goods, preserves/pickles, and beverages, in the categories of tastiest, biggest, prettiest/most creative, most interesting/funny-looking, and student grower (under 17).  The event is sponsored by the City of Cambridge, The Harvard Square Business Association, and Grendel’s Den.  Artwork by Philip Welsh.