Harrington Beach State Park covers 715 acres on the Lake Michigan shore in Ozaukee County, between the village of Belgium and the hamlet of Lake Church, roughly 40 minutes north of Milwaukee. The park protects more than a mile of shoreline, and the swimming here is open big-lake swimming: no roped area, no buoy line, no dock, just sand and cobble running into water that stays cold well past the start of summer. The Wisconsin DNR, which manages the park, says plainly that the lake can be dangerously cold, so use good judgment about whether to get in and how long to stay.

The shoreline is split into two named beaches. North Beach, reached by a paved path from the main parking area beside the Ansay Welcome Center, is the day-use swimming beach and does not allow pets. South Beach, farther down the park road, is the designated pet swim area, where dogs can be off leash while they are actually in the water and on an eight-foot leash the rest of the time. Both beaches get sampled for bacteria through the summer season, and any advisory or closure shows up on the DNR beach advisory map, so check it before you drive out.

The quarry lake is the question most people arrive with, and the answer is no. Quarry Lake is 26 acres of clear water left behind by the dolomite quarry that Lake Shore Stone worked from the 1890s until 1925, and the DNR prohibits both swimming and boating there. The same rule covers Puckett's Pond. Fishing is allowed from shore and from the Quarry Lake pier, with trout, crappies and bluegills the usual catch, and the park office loans out basic tackle at no charge. A trail loops the quarry, so you can walk the rim and look at water you are not permitted to swim in.

Entry takes a Wisconsin state park vehicle admission sticker. At the rates set in August 2025, a daily pass is 13 dollars for a car with Wisconsin plates and 16 dollars for out-of-state plates. A 12-month pass is 28 dollars for residents, 50 dollars for nonresidents and 13 dollars for Wisconsin residents 65 and older, who also pay just 3 dollars for a single day. The park is open 6 a.m. to 11 p.m. year round. Parking sits at the north end near the welcome center, at the south end, and in a walk-in and overflow lot by the campground. Access is better here than at most Lake Michigan beaches: the path to the sand is paved, and the park keeps a beach wheelchair anyone can check out for free, plus an accessible cabin, an accessible campsite, accessible picnic shelters and a universal playground.

The family campground has 69 sites, 31 with electric, plus a group site for up to 30 people, walk-in sites and a single kayak-in campsite for paddlers working their way along the Lake Michigan coast. Showers and flush toilets run during the summer season, and there is a dump station and a fresh water fill. Reservations go through wisconsin.goingtocamp.com or 1-888-947-2757. Elsewhere you will find picnic shelters, drinking water, vault toilets near the beaches and trailheads, and the Jim and Gwen Plunkett Observatory, open for monthly public viewings.

No lifeguard works anywhere in the park, and a wind shift can push the warm surface layer offshore and drop the temperature sharply in a few hours. Strong west winds are the other hazard. The DNR warns they blow small watercraft and inflatables away from shore, and with no boat launch in the park, help is not close. Rafts and boats need flotation devices aboard. The beach also holds industrial leftovers, including remains of a 700-foot pier that shipped cut limestone in the early 1900s and the anchor of the freighter Niagara, which burned in 1856, so watch your footing in the shallows.