Hacklebarney is the only place I will walk when the temperature is unbearable here in New Jersey. It is bordering a river so it always stays cool. The trails go down to the river and then up. You can continue up and down for over an hour of walking. Our dog loves it too. She can always get a drink. It is a very laid back park; rangers aren't walking around to see if your dog is off leash. We have never picnicked in Hacklebarney but there are lots of tables and grills. I think you could take a dip, too, if you wanted to.
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