anywhere in the parks where I can warm a bottle and warm some food. Baby won't drink a cold bottle or food and really don't want to bring a warmer into the parks with me and find a plug.
baby care centers would have a microwave but no outside food or bottles can be taken to the kitchens to be warmed. most will give you a cup of hot water to put bottle in to warm. based on my kids when they were little, you would be setting yourself up for very unhappy baby sitting in highchair for your meal having just ate at baby center