In the 3rd and 4th centuries A.D. , the Roman Emperor Avrelius the Third had built fortresses for the security of roads in Northern Bulgaria , which was under the rule of the Roman Empire at that time . Later on one of these fortresses is called Ryahova . In 1199 the Ryahova fortress was still used as a protection to the road that led to the capital city of the Second Bulgarian State , named Turnovgrad .

The Ryahova fortress is located 3 km west to the town of Gorna Oryahovitza and about 7 km north to Turnovgrad . The natural relief of the hill , its displacement and rocky terrain served as an excellent precondition so it was a good place for the fortress to be built .

Probably the choice of that place is taken as suitable because of the river Yantra which runs nearby the hills . The naturally created river ford reinforce the defensive role of the fortification of Ryahova .