Kremlins in Russia are fortified complexes that serve as the central government and historical sites. The most famous is the Moscow Kremlin, which houses important buildings like the Grand Kremlin Palace and the Cathedral of the Assumption. These structures reflect Russian architecture and history, dating back to the 15th century. Each major city in Russia may have its own kremlin, often built on elevated ground for defense. These sites typically include walls, towers, and cathedrals, showcasing the region's cultural heritage. Examples include the Kazan Kremlin and the Nizhny Novgorod Kremlin, each with unique architectural styles and historical significance.