Pliska was the capital of the First Bulgarian State between 681 to 893. Pliska National Historical and Archaeological Reserve has been declared an archaeological monument of national importance and included in the 100 National Tourist Sites. Pliska was the first capital of Bulgaria and the cradle of today's Bulgarian state. It is remarkable for its architecture, which was typial for previous Bulgarian settlements. Typically for a people coming from the steppes, Bulgarians built their capital in the middle of fields surrounded by hills as natural barriers to the invaders. There were three defensive lines built. The first defensive line is a deep ditch with a high embankment that encloses the peripheral town. The second defensive line is made of massive stone blocks forming a 12 m high fortress wall, which has 2 pentagonal towers and a gate on each wall, and the main entrance is on the eastern fortress wall. The third line is a brick fortification protecting the citadel. The entire walled complex is spread over an area of 0.5 sq. km. With its 23.3 sq. km., the town was gigantic for the medieval scale.