The Bulgarian calendar holidays and observances represent a social-cultural phenomenon that is rather complex in its origins and nature it took shape as a system in the process of consolidation of the Bulgarian nationality. The roots of the holiday customs, rites and rituals lead to ancient pagan concepts and beliefs, myths, cults and deities, through which man rationalizes recurring processes in nature, on which his life and labour depend to a great extent. The Bulgarian calendar holidays and observances are a part of the invaluable stock of the Bulgarian cultural heritage. Preserved through the centuries and helped us maintain our national identity, today they are still part of the contemporary festivities, keeping its ethnic originality. This national treasure that has maintained the spiritual make-up of our people is our contribution to the culture of the Europe. The “Bulgarian Calendar Holidays and Observances” encyclopaedia presents in a concise form the whole annual circle of holidays and observances our ancestors have left us. For each holiday the circle of folk notions, beliefs, ritual practices and items forming its core is given. Albeit not comprehensively, the regional specifics of the rituals and the terminology are presented. The description of the calendar holidays is supplemented by data on the Orthodox Christian calendar, a short hagiography of the holiday’s patron saint or the Christian legend related to this day, which serves to provide some background on the complex relation between paganism and Christianity. For the readers who want to follow the traditions in practice in their most accessible and preserved form - the food, we have compiled recipes for the main holiday dishes, arranged in the “Traditional Holiday Repast” appendix. The articles in the encyclopaedia “Bulgarian Calendar Holidays and Observances” have been arranged in an alphabetical order.