Büyükkale (Turkish for big castle) is a rocky ridge in the Hittite capital Ḫattuša, located in modern-day Turkey. It was inhabited from the late 3rd millennium BC during the early Bronze Age through to the Roman period. Prior to the arrival of the Hittites, a fortified settlement existed during the time of the Hattians, as well as during the period of the Assyrian trade colonies (the Karum period). During the Hittite Empire, the ridge was extensively developed and fortified, serving as the administrative seat of the Hittite Great Kings in the second half of the 2nd millennium BC. Fortified settlements also existed on Büyükkale during later Phrygian, Hellenistic, and Roman times. Since the early 20th century, the ridge has been thoroughly excavated, primarily by German archaeologists. The fortress is significant in Hittitology due to the discovery of numerous cuneiform tablets found in the building remains, written in Hittite as well as other languages.
Research history
The French traveler Charles Texier, who discovered the ruins near Boğazköy in 1834 and identified them as the remains of ancient Pteria, marked the fortress on his city plan as the Esplanade. The British geologist William John Hamilton, visiting in 1836, was the first to report on the pits or cisterns on the site and the numerous pottery sherds. In Carl Humann's more detailed 1882 plan, the fortress is labeled Böjük Kale. Excavations on Büyükkale began with the French archaeologist Ernest Chantre. After finding individual cuneiform tablet fragments in 1893, he conducted a test pit the following year, likely in the western part of the ridge. These discoveries sparked widespread interest, as they promised further insights into the ancient Near East. In 1905, German Assyriologist Hugo Winckler, along with Theodore Makridi, excavated at Boğazköy until 1907, likely at the same location as Chantre, focusing primarily on cuneiform texts while largely neglecting the architecture. Numerous clay tablets were uncovered, leading Winckler to conclude that the ruins at Boğazköy were those of Ḫattuša, the capital of the Hittite Empire. These unsystematic and unpublished excavations were partially documented by Otto Puchstein, who was present at the time.
From 1907 to 1931, excavations on Büyükkale were halted, partly due to World War I. In 1931, German prehistorian Kurt Bittel, commissioned by the Archaeological Institute of the German Reich (now the German Archaeological Institute) and the Deutsche Orient-Gesellschaft, resumed excavations at Boğazköy, initially focusing on Büyükkale. Within the next two years, large quantities of cuneiform tablets were unearthed. These finds prompted continued excavations, which now systematically documented architectural remains from various layers. Under Bittel's direction, with support from the German Archaeological Institute, the German Research Foundation, and various sponsors, excavations continued until 1939 and resumed in 1952 after a war-related interruption, with the collaboration of architect and archaeologist Rudolf Naumann. From 1954 to 1966, Peter Neve led the Büyükkale excavations, taking over the overall direction of Ḫattuša excavations in 1978. His successor, Jürgen Seeher, led from 1994, followed by Andreas Schachner since 2006. Finds and contexts have been regularly published since the early 20th century in the journals Mitteilungen der Deutschen Orient-Gesellschaft and Wissenschaftliche Veröffentlichungen der Deutschen Orient-Gesellschaft. The first comprehensive architectural survey was published by Peter Neve in 1982, titled Büyükkale – Die Bauwerke.
The finds are displayed in the local Boğazköy Museum, the Çorum Archaeological Museum, and primarily the Museum of Anatolian Civilizations in Ankara.
Location The rocky ridge, composed of Mesozoic limestone, is part of a mountain range that encloses the Budaközü Çayı valley to the east. Oriented from southwest to northeast, the high plateau measures approximately 260 × 150 meters. Its highest point, a rock barrier in the northeast, reaches 1,128 meters above sea level. Before construction, the surface was more rugged than it appears today, having been significantly leveled through building activities and natural processes. The plateau is naturally protected by steep cliffs in the north and east, with gentler slopes in the south and west. It lies in the eastern center of Ḫattuša, at the boundary between the Upper and Lower City. The city wall separating the Lower City from the younger Upper City, known as the Postern Wall, also forms the southern fortification of the fortress. It encircles the old city in a wide arc, reconnecting with the northern fortification of Büyükkale. South of the ridge lies the Südburg, a hill that housed a sanctuary with a hieroglyphic chamber and later a Phrygian fortification. Southwest, where the entrance is located, a modern road passes at the base of the hill, descending from the Lion Gate. Across the road to the west lies the Nişantepe rock with the Nişantaş inscription of Šuppiluliuma II. The ridge offered a commanding view over the Lower City and much of the Upper City.
History
The earliest traces of settlement in Ḫattuša date to the Chalcolithic period in the 6th millennium BC, found on the Büyükkaya ridge north of Büyükkale. Büyükkale itself was inhabited from the late Early Bronze Age, with the earliest evidence being storage pits in the south and southwest of the plateau. Their dating is uncertain but predates 2000 BC. Settlement expansion began thereafter, initially limited to the southern part but featuring fortifications by the 19th century BC. The pre-Hittite Hattians are likely candidates for its inhabitants. The entire city of Ḫattuša, including Büyükkale, was destroyed in a conflagration around 1700 BC by Anitta of Kaniš. Resettlement began about a century later, around 1600 BC, when the city was refounded by Ḫattušili I. Likely due to raids by the Kaska, Ḫantili I constructed the first city wall at the turn of the 17th to 16th century BC, which he claimed was previously unprotected, likely identical to the Postern Wall forming the southern fortification of Büyükkale. Due to throne disputes starting under Ḫantili, the city experienced economic and political decline, exploited by neighbors, leading to another burning and gradual decay. The Proclamation of Telipinu by Telipinu after 1500 BC regulated succession, ending internal conflicts and stabilizing rule, enabling the city's rebuilding. On Büyükkale, a systematic palace complex was first developed. It was destroyed again after 1280 BC, likely linked to succession disputes between the designated ruler Urḫi-Teššup (Muršili III) and his uncle, later Great King Ḫattušili III. The latter and his son, Tudḫaliya IV, oversaw the reconstruction of the final imperial palace, which was destroyed with the fall of the Hittite Empire around 1180 BC.
From the 8th to 6th centuries BC and during Roman times, the plateau was inhabited and usually fortified but never regained regional significance. No further historical details are known.
Structure The fortress ridge was developed in multiple construction phases and layers. An initial classification into five layers was established in the 1930s, numbered from top to bottom: Layer I Layer II – both post-Hittite Layer IIIb Layer IIIa – both imperial period Layer IV – Old Hittite This classification was later refined and expanded but retained its core structure despite some limitations, such as not fully capturing the sparse Roman and Byzantine periods. The current classification is as follows:
Layer Period Byzantine Roman Imperial Hellenistic Ia Late Phrygian Ib IIa Early Phrygian IIb III Hittite Empire IVa–b IVc Old Hittite IVd Karum period Va Vb Vc Pre-Hittite Vd–f Vg Before 2000 BC Each layer may encompass multiple construction phases.
The following description reflects the state of the late imperial period in the 13th century BC (Layer III).
Pre-Hittite period The earliest evidence includes several round pits dug into the clay in the south and southwest of the plateau, near the later Upper Citadel Court, in the area of later buildings M and N. Varying in size, these pits are 0.25 to 0.95 meters deep with diameters of 0.60 to 1.95 meters, likely used as storage silos and later as refuse pits. Finds include fragments of a Chalcolithic pithos, painted sherds of Alişar-III ware, and monochrome sherds, both handmade and wheel-thrown. Precise dating is not possible, but their origin is attributed to Layer V.
From pre-Hittite layers Vd–g, various foundation remains, primarily in the southern plateau, were identified. Built of rubble stones, their purpose is unclear, though a strong southern wall near the later Citadel Gate Court suggests a defensive structure, indicating a fortified presence. Finds include handmade ceramics, Alişar-III ware, and thin-walled wheel-thrown "flowerpot" ware. Layer Vd includes a spatula-like bronze tool. In Layer Vc, near the later Lower Citadel Court, several houses with clay floors were identified, some retaining stone foundations and mudbrick walls. The largest, with eight rooms across three terraces, yielded two charred door leaves (85 × 180 cm), suggesting it was a residence for a high-status individual. Another building likely had two stories. Finds included pithoi, tableware, hearths, pot stands, a stone mold, a bone pin, seals, burnt grain, and a human skeleton. These structures were destroyed in a fire, dated between 1800 and 1600 BC via radiocarbon dating of wood fragments.
Karum period From pre-Hittite layers Va and Vb, only sparse foundation remains survive, as they were systematically overbuilt, dismantled, or leveled by Layer IVd. These contained few remnants of hand- and wheel-made ceramics, with uncertain dating. Layer IVd is securely dated to the Karum period. It includes parts of a over four-meter-wide wall at the Lower Citadel Gate, the earliest evidence of fortification, possibly built on older wall debris. Various building remains were excavated in the south and southwest, mostly wall fragments, except for Building I/IVd, measuring 23 × 21 meters with at least twelve rooms, some two-storied, and a courtyard with a hearth. Finds in the courtyard included abundant tableware, half a red deer antler from a meal, and a child's skeleton, suggesting use as a burial site. Room finds included pithoi, decorated spouted and handled jugs, bowls, painted tower vases, and animal rhyta in lion and duck shapes, both utilitarian and cultic. Other finds included a grindstone, lead sheet, bronze pins, and over 100 clay lumps with seal impressions (1 cm diameter) showing ornaments and stylized figures. Layer IVd dates to the 19th century BC during the Assyrian trade colonies, ending in a devastating fire at the 18th–17th century transition during Anitta's attack from Kuššara.
Early Hittite period
Layer IVc, from the Old Hittite period, includes settlement remains across the plateau and structures on the southwestern slope. Most buildings on the slope are sparsely preserved, overbuilt by the Postern Wall, the earliest Hittite city fortification, constructed in the final phase of IVc. It extended northwest from Büyükkale, encircling the emerging Lower City, partly overbuilt by modern Boğazkale, and reconnected to Büyükkale's northern wall. Built without mortar from two roughly dressed rubble stone walls (each ~2.7 m thick) filled with gravel and fieldstones, it had a total thickness of 7.5 meters. At the southwestern base, a gate structure had an inner passage of 3.6 meters and an outer one of 3.8 meters, flanked by two gate chambers (11 m wide, 3.5 m deep in the east, 3.0 m in the west). Finds in this area, mostly redeposited from earlier phases, include two arm-thick clay pipes, closed at one end with a thin nozzle-like perforation, likely used for kiln ventilation due to glass flux at the nozzle.