Stirling Castle, located in Stirling, is one of the largest and most historically and architecturally important castles in Scotland. The castle sits atop an intrusive crag, which forms part of the Stirling Sill geological formation. It is surrounded on three sides by steep cliffs, giving it a strong defensive position. Its strategic location, guarding what was, until the 1890s, th…Stirling Castle, located in Stirling, is one of the largest and most historically and architecturally important castles in Scotland. The castle sits atop an intrusive crag, which forms part of the Stirling Sill geological formation. It is surrounded on three sides by steep cliffs, giving it a strong defensive position. Its strategic location, guarding what was, until the 1890s, the farthest downstream crossing of the River Forth, has made it an important fortification in the region from the earliest times.