There are no restaurants near there but there is a very small campground store just up the road to get some basic staples, ice and ice cream.
There are no restaurants near the dunes. Alamosa is the closest I know of near there.
Great Sand Dunes Oasis offers food and it is right next to the entrance to the park.
Food is about 40 minutes away. Pack food lots of places for picnics
Hurricane Utah is just down the road with anything you want food wise.
Nothing to speak of.
Watch the hours for places to get supplies.
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