The village of Kalen (Vratsa District) is located in North-West Bulgaria and is included in Municipality Mezdra. It is tiny but nice village and is lately developed as destination for ecotourism and villa zone for people from Sofia. The area is mountainous with large forests and caving systems. There are frequent buses to Mezdra and Vratsa (both are around 18km away from Kalen) and one daily bus to and from Sofia.