The Air Defense Museum in Hyrylä, Tuusula, showcases the history and equipment of Finland’s air defense. In the exhibition halls and outdoor area, visitors can learn about the development of the country’s defense and explore equipment from different eras. The museum grounds also include the historic Kapteenin puustelli. The rotating fall exhibition, “The Unbreakable Code,” explores military communications and cryptography. During the winter season, the museum is open to the public from Wednesday through Sunday; the Tuesday opening hours offered during the summer are not guaranteed for fall visits.