I go to the dragon locations in Skyrim, but there are no dragons. I've looted the chest and learned the word, but there are no dragons to be seen. I'm playing on a 360.
You need to reach a certain point in the main questline.
Upon the start of the quest "A Blade in the Dark", Alduin will begin to revive dragons from their burial mounds scattered across Skyrim.
You need to finish the 2nd battle in the main questline 'Dragons Rising' you need to do this to get your shouts this is the ONLY way to get dragons to start to spawn.
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