State-of-the-art of historical earthquake investigation in Bulgaria

This paper deals with non-instrumental seismology development in Bulgaria (the central-eastern part of the Balkan peninsula). The first steps and products of this scientific branch are discussed because they have traced the road of present-day historical seismology in this country. The sources of information on long-term seismicity are critically reviewed. Some recent studies, which contribute to an improvement of the supporting data sets, are also discussed. A special emphasis is laid on the rules adopted to solve different cases as well as on the aspects, by which our understanding of the seismogenesis throughout the present-day Bulgarian lands has been enhanced