The main beach at East Fork State Park is a 1,200-foot strip of sand on the south shore of William H. Harsha Lake, the 2,160-acre reservoir that many locals still call East Fork Lake. The Ohio Department of Natural Resources runs the park, while the U.S. Army Corps of Engineers built and operates the dam that holds the lake back on the East Fork of the Little Miami River. The park sits in Clermont County about 25 miles east of downtown Cincinnati, a few miles north of the village of Bethel.

To reach the beach, come into the south side of the park on Elklick Road (Park Road 1), passing the park office at 3294 Elklick Road, and turn north onto Beach Road, which older maps label Park Road 2. The road ends at large paved lots just above the sand, next to the Matt Maupin Pavilion. The Main Beach area is open to cars from 8:30 am to dusk. The park as a whole keeps hours of 6 am to 11 pm daily. There is no entrance fee, parking fee or beach fee. Ohio does not charge admission at its state parks, and the $3 visitor pass at East Fork is for visitors to the campground (Memorial Day through Labor Day), not the beach.

Swimming is allowed inside the buoyed area during daylight hours, and there is no lifeguard. The sand turns coarse and pebbly right at the waterline, so water shoes help. Harsha Lake allows unlimited horsepower boating, and on busy summer afternoons wakes and wind chop roll in from the open lake beyond the swim buoys. A beach house has changing booths and men's, women's and family restrooms. Dogs are allowed on leash elsewhere in the park but not on the sand. The park invites visitors to bring their own volleyball, soccer or cornhole gear for games on the beach.

Take the safety side seriously. Two people drowned at Harsha Lake over the Fourth of July weekend in 2025, one pulled from the marked swim area and a 14-year-old found outside it. Stay inside the buoys and keep a close eye on children. Harmful algal blooms are the other recurring problem. The park's beaches were posted with microcystin advisories in 2014, 2016 and 2021, and in some years the county told people and pets to stay out of the water entirely. The Ohio Department of Health posts weekly sampling results for this beach on its BeachGuard site from Memorial Day to Labor Day, and the park posts advisory signs at the beach giving the current toxin level whenever a bloom is detected. Check before you go.

There is plenty to do around the beach. A hand-launch ramp for kayaks and canoes sits just east of the sand, with a life jacket loaner board. The half-mile Storybook Trail starts nearby, and the Indian Mound picnic area and the Adena-era Elk Lick Mound are a short drive back up Elklick Road. Beyond that, the park has more than 400 campsites on the north shore (with its own smaller campground beach for campers), dozens of miles of hiking, bridle and mountain bike trails including the 33-mile perimeter trail, and eight boat ramps around the lake.