The village of Mladejko is located in South-East Bulgaria and is included in Municipality Malko Turnovo (Bourgas District). It is situated 50 km south from Bourgas at one of the Mladezhka River sources. The area abandons in caves, some of which were inhabited by men in the XII - VIII century B.C. Mladejko is also the site of the largest Thracian and Late Antiquity fortress in the Strandja mountain (covering an area of more than 4 hectars), whose ruins can be seen about a mile away from the village.