I really enjoy this show. I'm really glad they're making more DreamWorks dragons content. However, unlike the original show and movies, the runes in the show are gibberish. They are real ruins but they don't actually spell anything like they did in the movies and other shows.
It looks like they are using Anglo-Saxon Futhark. The previous shows and movies used elder.
It's a real disappointment and a let down as I taught myself elder Futhark and I enjoyed pausing and reading the runes myself.