Dune buggy

The Oregon Coastal Dunes Park ecology and geology is so-o-o-o interesting. The dunes are several hundred feet high (as much as 500 feet) and extend up to a mile inland (and stretch for 40 miles along the coast).
Source of the sand is from sediment deposited at the mouth of rivers, then the ocean currents pick it up and move it south until it hits a projecting head of land, then it starts to build up and the wind carries it inland.
There are forests growing in AND on it.  There are several phases of forestation but the most interesting is the old forest which still grows from the floor of the valley (under the dunes) and out the top of the sand. We're talking about maybe 100 feet down in the sand; branches have turned down into the sand and become roots, and new green growth is maybe another 50 plus feet above the sand surface.
Then there is the new forest which has grown on top of the sand once the sand has stabilized.
There is much ATV and dune buggy activity as you can imagine, but a good portion is trails thru trees just like any forest trails, only the sand is hundreds of feet above the beach elevation.
We chickened out on the individual ATV rentals, but took a tour in a modified suburban type vehicle .... which was much more exciting and hair raising than if we had driven our own.  We got about half an hour of just riding the dunes .... fast..... and steep.  I think just because we are three 'old ladies' we got the special roller coaster version. 
It was fun ! ..... right up there with whitewater rafting.
Later,
Marilyn