The fortress evolved in stages. The first recorded attempt to replace the original wooden fort with stone dates to 1374, when the Dmitrovskaya Tower was built. That tower has not survived, but its name persists in the replacement that stands today. Under Ivan III, Nizhny Novgorod became a garrison city tasked with marshaling troops for Moscow's wars against the Khanate of Kazan. Construction of the stone kremlin began in earnest in 1500 with the Ivanovskaya Tower, and by 1515 a two-kilometer wall reinforced by 13 towers encircled the hilltop. A massive fire in 1513 had already destroyed the old oak fortifications, lending urgency to the project. One tower, the Zachatskaya, stood on the banks of the Volga itself. A landslide swallowed it in the 18th century; it was not rebuilt until 2012.

Inside the kremlin, the oldest surviving building is the Michael the Archangel Cathedral, constructed no later than the mid-16th century and rebuilt between 1628 and 1631. It holds the tomb of Kuzma Minin, the merchant who, alongside Prince Dmitry Pozharsky, organized the volunteer army that expelled the Polish-Lithuanian occupiers from Moscow in 1612 -- an event so central to Russian identity that it is still commemorated as a national holiday. An obelisk honoring both men was erected in front of the cathedral in 1828. Other buildings accumulated over the centuries: the military governor's house (1837-1841, now the Museum of Art), an arsenal built at Nicholas I's direction between 1840 and 1843, and the House of Soviets, which in 1931 replaced a Transfiguration Cathedral that had stood on the same ground.

When the Second World War came to Gorky -- as Nizhny Novgorod was then known -- the kremlin returned to its original purpose. The roofs of the Taynitskaya, Severnaya, and Chasovaya towers were dismantled and anti-aircraft machine guns installed on their upper platforms. The Luftwaffe targeted the Kanavino bridge and the nearby fairground, but the kremlin's improvised air defenses helped protect these vital structures. The city earned the title "City of Labour Valour" for its wartime industrial contributions, manufacturing tanks, planes, and artillery shells. Since 1980, a military-patriotic memorial called "Gorky for the front!" has displayed the equipment the city supplied to the Eastern Front. A granite slab at its entrance bears words from a 1942 edition of Pravda: words of recognition for those who forged weapons and cooked steel alongside those who carried rifles.

In October 2018, archaeologists working on the site of the destroyed Church of St. Simeon Stylites discovered the remains of a medieval settlement and cemetery within the kremlin walls. The finds dated to the 13th century, with the most ancient cultural layer reaching back to 1221 -- the year Nizhny Novgorod was founded. The discovery pushed the tangible archaeological record of the site to the city's very origin. It also underscored how much history remains buried beneath the fortress: centuries of occupation, worship, and daily life compressed into layers of earth behind walls that have themselves been rebuilt, reinforced, and restored through war, neglect, and ambition.

For 230 years, the interior "battle road" -- the walkway inside the kremlin wall that soldiers once patrolled -- was closed to the public. Before the city's 800th anniversary in 2021, a major restoration reopened the full two-kilometer circular route. Visitors can now walk the entire perimeter within the wall, passing through or alongside all 13 surviving towers. The Chasovaya (Clock) Tower still keeps time. The Koromyslova Tower carries a legend about a woman with a yoke who single-handedly defeated a raiding party. From the Dmitrievskaya Tower, the main entrance since the fortress was first built, the view opens across the confluence of two of Europe's great rivers. In 1949, the Council of Ministers ordered the kremlin's restoration. It took decades -- and the work, in many senses, continues still.