The Oregon Dunes Overlook and Day Use is a park near milepost 200 on US 101. It's a lovely spot, run by the U.S. Forest Service as part of the Oregon Dunes National Recreation Area. It offers parking, rest rooms, water, platforms overlooking an expanse of Oregon's picturesque coastal dunes, and accesses 113 and 114 to a 4.8-mile trail loop across the dunes to the ocean beach, down the beach, and back paralleling Tahkenitch Creek.
Dina Pavlis included this spot as one of two hikes to give the flavor of the Oregon Dunes to visitors in her book, Secrets of the Oregon Dunes. If you are a fan of the Oregon Coast, you should check this out.
Read more at Secrets of the Oregon Dunes, 100 Steps, Frommer's, MySouthLane.com, Oregonhikers.org, Outdoor Project, Siuslaw National Forest, U.S. Forest Service, and Google Image Search.