Ike Kinswa State Park juts out on a small peninsula where the Cowlitz River meets dam-created Mayfield Lake, making it a good location for swimming, fishing, and boating. The park encompasses 454 acres along 9 miles of shoreline. Located between Olympia and Mt St Helens near the town of Mossyrock, it is about a 2 hour drive from either Seattle or Portland.

The park is named for a Cowlitz Indian representative, since the Cowlitz originally lived in the area and their ancestors’ graves needed to be moved when the dam filled in the valley to form the current lake.

The main campground is oriented to cars, RVs, and boaters. It sometimes has a bit of a local party atmosphere, so bring earplugs in case any revelers are nearby. Unmuffled speed boats sometimes roar past the forest as well. The campground is formed by several loops, all of which are in easy walking distance to the river and lake. During the summer, the one way loop roads are filled with kids on bicycles and walkers. Each loop has a bathroom in the center with pay showers. The campground is open year around, and there are also 5 rustic cabins available.

After crossing over route 122 to the north side, the road ends at a big parking lot by a large swimming area on Mayfield Lake. A grass lawn slopes gently to the water’s edge. The swimming area is protected by floating buoys to keep swimmers in and boats out. Unfortunately there is a large population of geese present when people are not around, so there can be lots of goose poop to step over or see disintegrating in the water. The water can also be turbid from all the swimmers stirring up the bottom.

I found the privacy and cleanliness on the Cowlitz River side to be much better than the official Mayfield Lake swimming area. However, the water was a bit colder on the river side as compared to the shallow sun-soaking expanse on the lake side.

Overall, Ike Kinswa State Park is a good park for family-oriented activities, car-camping, and water fun.

Cowlitz River from Ike Kinswa State Park near towns of Silver Lake and Mossyrock

Cowlitz River by Ike Kinswa State Park

Ike Kinswa State Park swimming area on Mayfield Lake

Mayfield Lake swimming area

Ike Kinswa State Park
Cowlitz River
Lake Mayfield

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