A unique military-engineering structure from the early 16th century still retains the appearance of a medieval fortress with multi-tiered towers and impregnable walls pierced by narrow loopholes. The stone kremlin was built to protect the southeastern borders of the Moscow state, using the most advanced technologies of the time.

The shape of the fortifications is an irregular polygon with towers at the corners. Originally, the defensive complex included 14 towers, including an additional fortification in front of the Dmitrievskaya Tower, a shooting gallery. Today, the kremlin has 13 towers. The length of the walls exceeds 2 km, their height with battlements reaches 12 m, and the thickness at the base is 5 m. The height of the towers varies from 18 to 30 m. Throughout its long history, the kremlin has witnessed many vivid and dramatic events, but thanks to excellent defensive organization, it has never been captured.

The main visual dominant of the elevated part of the kremlin is the Dmitrievskaya Tower, once the main defensive node, adorned with a gilded emblem of the city, a walking deer. An important architectural landmark of the western part of the kremlin is the Cathedral of Archangel Michael, a unique monument of temple architecture from the 17th century.

In the early 18th century, the kremlin lost its military significance and became a monument of antiquity. In 1896, the Dmitrievskaya Tower, reconstructed according to the design of architect N. Sultanov, housed an art and historical museum.

From 1949 to 1977, the kremlin underwent restoration under the guidance of Professor S.L. Agafonov. After the collapse of the USSR in 1991, restoration work ceased. Around 2005, dangerous cracks appeared on the walls of the kremlin, and the brickwork began to crumble and become covered with moss. Since 2005, restoration work has resumed, but not always at the proper level, leading to distortions in the appearance of the fortress.

The use of the fortress as a tourist attraction has deteriorated due to improper use and the transfer of towers to third-party organizations. Trade pavilions for selling souvenirs were set up in the niches of the kremlin wall. Souvenir shops were also located in the passage of the Dmitrievskaya Tower, but they were eliminated in 2020. Food establishments operate in the converted Store Tower and niches near the Dmitrievskaya Tower.

In 2012, the Zachatyskaya Tower was recreated, closing the ring of the kremlin walls. A new government building has been constructed on the territory of the kremlin, next to the Legislative Assembly of the Nizhny Novgorod region.

In October 2018, archaeologists discovered the remains of a medieval settlement and cemetery at the site of the destroyed Church of St. Simeon Stylites. The finds date back to the 13th century, with the oldest cultural layer dating to 1221, when Nizhny Novgorod was founded. The discovered items were museumified, and in June 2020, the restoration of the Simeon Church began. The reconstruction of the bell tower of the Transfiguration Cathedral and the restoration of the military riding hall, where a church existed before the revolution, have also begun. The restoration of the kremlin's temples is timed to the 800th anniversary of the city in 2021.