Abdullakhan Kala was grown in just a few decades in borders and reached the limits of the fortress walls. Rural part, consisting of tents and mud huts, left defenseless against numerous invasions. As a result, in the middle of the 15th century Mirza Sanjar started construction of a new city, providing the ditch and defensive walls. This ruler was the great-grandson of Tamerlane and the continuation of the great Timurid. The new city was attached to the western strengthen Abdullakhan Kala. From the height he was an elongated rectangle with sides of 500 and 750 meters. Area of the city exceeded 37 hectares. In the citadel of Bairam-Ali-Khan-Kala located ruler of the palace, a mosque, souks, madrassas, khanaka, baths and craft workshops.
Alisher Navoi’s poem tied Sanjar’s name on the birth of New Merv.
At that time, military campaigns are not ended, continuously someone attacked, robbed and hijacked. The fertile oases and prosperous city like a magnet attracts everyone, whether local feudal lords, Uzbeks, Bukhara, Persians and Khivans repeatedly attacked the new Merv. As a result of the settlement were only areas of the northern and southern walls, turned into ruins.
At the end of the XVIII century fort to get killed in the name of fighting Bairam-Ali Khan, who was at the head of the fortress for three years.