The first Oregon dunes were formed between 12 and 26 million years ago by the weathering of inland mountain ranges, but it was not until about 7,000 years ago, after the massive eruption of the Mount Mazama volcano, that they reached their current size and shape. That volcanic eruption emptied out the entire molten-rock contents of Mount Mazama, and in the process created the caldera that would later become Crater Lake.

Due to water currents and winds, the dunes today are in constant flux. Currents move the sand particles north each winter and south each summer, while constant winds off the Pacific Ocean blow the sand eastward, piling it up into dunes that are slowly marching east. Over thousands of years, the dunes have swallowed up forests, leaving some groves of trees as remnant tree islands.

Freshwater trapped behind the dunes has formed numerous freshwater lakes, many of which are now ringed by campgrounds and vacation homes. These lakes are popular for fishing, swimming, and boating. The largest of the lakes lie outside the national recreation area and are, from north to south, Woahink Lake, Siltcoos Lake, Tahkenitch Lake, Clear Lake, Eel Lake, North Tenmile Lake, and Tenmile Lake. Smaller lakes that are within the recreation area include Cleawox Lake, Carter Lake, Beale Lake, and Horsfall Lake. Traditionally, these lakes have been in a constant state of flux; with the construction of homes around their shores, though, the lakes are now maintained at their current shape and size.

European beach grass is playing an even greater role in changing the natural dynamics of this region. Introduced to anchor sand dunes and prevent them from inundating roads and river channels, this plant has been much more effective than anyone ever imagined. Able to survive even when buried under several feet of sand, European beach grass has covered many acres of land and formed dunes in back of the beach. These dunes effectively block sand from blowing inland off the beach, and as winds blow sand off the dunes into wet, low-lying areas, vegetation takes hold, thus eliminating areas of former dunes. Aerial photos have shown that where once 80% of the dunes here were open sand, today only 20% are. It is predicted that within 50 years, these dunes will all have been completely covered with vegetation and will no longer be the barren, windswept expanses of sand seen today.

There are numerous options for exploring the dunes. Jessie M. Honeyman Memorial State Park (tel. 541/997-3641;, 3 miles south of Florence, is a unique spot with a beautiful forest-bordered lake and towering sand dunes. The park offers camping, picnicking, hiking trails, and access to Cleawox and Woahink lakes. On Cleawox Lake, there is a swimming area and a boat-rental facility. The dunes adjacent to Cleawox Lake are used by off-road vehicles.

The easiest place to get an overview of the dunes is at the Oregon Dunes Overlook, 10 miles south of Florence. Here you'll find viewing platforms high atop a forested sand dune that overlooks a vast expanse of bare sand. Another easy place from which to view the dunes is the viewing platform on the Taylor Dunes Trail, which begins at the Carter Lake Campground, 7 1/2 miles south of Florence. It is an easy 1/2-mile walk to the viewing platform.

There are several places to wander among these sand dunes. If you have time only for a quick walk, head to Carter Lake Campground, where you can continue on from the Taylor Dunes viewing platform. The beach is less than a mile beyond the viewing platform, and roughly half this distance is through dunes. From this same campground, you can hike the Carter Dunes Trail. The beach is 1 1/2 miles away through dunes, forest, and meadows known as a deflation plain. A 3.5-mile loop trail leads from the Oregon Dunes Overlook out to the beach by way of Tahkenitch Creek, a meandering stream that flows through the dunes and out to the ocean. Another mile south of the Oregon Dunes Overlook, you'll find the Tahkenitch Trail Head, which accesses an 8-mile network of little-used trails that wander through dunes, forest, marshes, and meadows. However, for truly impressive dunes, the best route is the John Dellenback Dunes Trail, which has its trail head a half mile south of Eel Creek Campground (11 miles south of Reedsport). This 3-mile round-trip trail leads through an area of dunes 2 miles wide by 4 miles long. Don't get lost!

About 30% of the sand dunes are open to off-road vehicles (ORVs), which are also known as ATVs (all-terrain vehicles), and throngs of people flock to this area to roar up and down the dunes. If you'd like to do a little off-roading, you can rent a miniature dune buggy or ATV from Sand Dunes Frontier, 83960 U.S. 101 S. (tel. 541/997-5363;, 4 miles south of Florence. Guided tours of the dunes are offered by Sand Dunes Frontier and Sandland Adventures, 85366 U.S. 101 S. (tel. 541/997-8087;, 1 mile south of Florence (this company has a little amusement park as well). The tours cost about $12 to $45. One-person dune buggies and ATVs rent for about $45 per hour. Down at the southern end of the recreation area, you can rent vehicles from Spinreel Dune Buggy Rentals, 67045 Spinreel Rd., North Bend (tel. 541/759-3313;, located just off U.S. 101, about 9 miles south of Reedsport.

Ever heard of sand boarding? It's basically snowboarding in the sand, and at Sand Master Park, 87542 U.S. 101 N., Florence (tel. 541/997-6006;, you (or your teenage kids) will find 40 acres of sculpted sand dunes designed to mimic a wintertime snowboard park (lots of jumps and rails). June through mid-September, the park is open daily from 9am to 6:30pm; other months, it's open Monday through Tuesday and Thursday through Saturday from 10am to 5pm, and Sunday noon to 5pm. The park is closed from mid-January through February. Sand boards rent for $10 to $35.

If you'd rather avoid the dune buggies and ORVs, stay away from the dunes between the South Jetty area (just south of Florence) and Siltcoos Lake; the area adjacent to Umpqua Lighthouse State Park just south of Winchester Bay; and the area from Spinreel Campground south to the Horsfall Dune & Beach Access Road, which is just north of the town of North Bend.

Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.