You can take Route 25A into Kings Park, turn on to Old Dock Road north. Take it to the end which will put you at the Smithtown boat ramp, and a beach area on the south side of the river. You can also take the Sunken Meadow(Sagtikos)Parkway north to the end. This will bring you into Sunken Meadow Park. Drive to the eastern most parking lot, and walk the beach east to the Kings Park bluffs, better known as the "Point." This is the mouth of the Nissequogue. For night fishing..you need a special permit that you can get from the State Parks office.