Religious festivals, patron saints and traditional holidays mark the Azorean calendar. The most important religious events are tied with the festivals associated with the cult of the Holy Spirit, commonly referred to as the festivals of the Holy Spirit (or "Espírito Santo"), rooted in millenarian dogma and held on all islands from May to September. These festivals are very important to the Azorean people, who are primarily Roman Catholic, and combine religious rituals with processions celebrating the benevolence and egalitarianism of neighbours. These events are centred around "treatros" or "impérios", small buildings that host the meals, adoration and charity of the participants, and used to store the artefacts associated with the events. On Terceira, for example, these impérios have grown into ornate buildings painted and cared for by the local brotherhoods in their respective parishes. The events focus on the members of local parishes, not tourists, but all are welcome, as sharing is one of the main principles of the festivals. Some limited events focus on tourists, including a public event that the city government of Ponta Delgada on the island of São Miguel holds, which attracts visitors and locals.