Open all day and night year round, the tallest dunes in North America are the centerpiece of the Great Sand Dunes National …by markAugust 9, 2020 Open all day and night year round, the tallest dunes in North America are the centerpiece of the Great Sand Dunes National Park in Colorado. Great spot to clear your head. Share this:TwitterFacebook Leave a Reply Cancel replyYour email address will not be published. Required fields are marked *Comment Name * Email * Website Save my name, email, and website in this browser for the next time I comment. Notify me of follow-up comments by email. Notify me of new posts by email.