Yes. According to Danish legislation, it is mandatory to receive Euro.
Black sun is from late August to October. You can get both guided tours and even find places to see the beautiful sight. read much more in our black sun guide.
You will find the Wadden Sea along the West Jutland coast and it would be a good idea to check the tide before heading off to the coast.
You can always try to call or write to our tourist information. You can also try searching our brochure.
Yes, it is 100% free to visit beaches in Denmark
You can always find our hiking and biking trails in our guides which you can read here on the site, or you can always visit our tourist information where we have brochures around the routes.