The city Nebuchadnezzar built
Most of what visitors imagine when they think of Babylon dates to the sixth century BCE, in the reign of Nebuchadnezzar II (about 605 to 562 BCE). He rebuilt temples and palaces, strengthened the fortifications and gave the city a monumental ceremonial centre. His inscriptions, stamped on bricks across the site, record his work in a repeated formula, and they are one reason his buildings are so easy to identify. Earlier and later levels exist, but they are far less well known because the water table limited excavation.
The building materials explain a lot. Babylonia had little stone and almost no timber, so builders relied on mud brick and baked brick, joined with bitumen or clay mortar. This was an old tradition, already well established in Sumerian architecture more than a thousand years earlier. Baked brick was costly and was used for outer faces, important walls and places that would meet water. This is also why so little of the original skyline remains standing: mud brick erodes quickly once the protective surfaces fail.
The Ishtar Gate
The Ishtar Gate was one of several gates in the inner city wall, on the north side, and was dedicated to the goddess Ishtar. In its best-known phase it was a pair of towers decorated with glazed bricks in deep blue, with rows of animals in relief in yellowish and white tones. The animals alternate between the aurochs (a wild bull) and the mushussu, a serpent-dragon associated with Marduk. Lions, associated with Ishtar, decorated the walls of the road leading to the gate. The gate seems to have been rebuilt and raised more than once, and the animals visible in the reconstruction come from the later phases.
Glazed brick was an expensive technique that involved moulding the brick, applying a coloured glaze and firing it. The result stayed bright in a way that painted plaster did not. The same technique appears elsewhere in the Near East, and a later example is the glazed brick friezes in the city of Susa under Persian rule. The Ishtar Gate was both defence and display, announcing the power of the king to anyone entering the inner city.
The Processional Way
North of the main temple area, the Processional Way ran from the Ishtar Gate through the city towards the Esagila temple of Marduk. It was paved with limestone slabs set on a bed of brick and bitumen, and its walls were decorated with lions on glazed brick. It served for religious processions, especially at the new-year festival, when the statues of gods were carried through the city. Its ancient name is usually given as a phrase meaning “may the enemy not pass”, though the exact meaning is discussed. Its stone paving was a rare luxury in a land without local quarries.
Walls and defences
Babylon had a double wall around the inner city, and a wider outer circuit enclosed more ground. These were backed by moats fed from the Euphrates. The ancient Greek writer Herodotus described the walls as so wide that chariots could ride on top, and gave figures for height and length. Modern scholars treat his numbers with caution, since they seem to be exaggerations, but the excavated walls were certainly massive. Their purpose was partly protection against Assyrian-style sieges and partly prestige.
The Etemenanki ziggurat
Near the Esagila stood the ziggurat Etemenanki, whose name means “house of the foundation of heaven and earth”. A later cuneiform tablet describes it as a tower of seven stages. Only the foundation survives, a square pit of brick marks, because later builders removed the brick. Some people link Etemenanki to the Tower of Babel in the Bible; this is possible as an influence on the story, but the connection is debated, and the biblical text itself does not name the tower. Alexander the Great is said to have ordered the clearing of the ruins before his death, which suggests that the structure was already damaged.
The palaces
The Southern Palace, the largest of Nebuchadnezzar’s royal residences, was built around a series of courtyards. Its throne room had a facade decorated with glazed brick showing lions, palm trees and floral patterns. The comparison with Assyrian palace reliefs is instructive: Assyrian kings decorated palaces with stone relief carved in the narrative of war and hunting, while Babylon used coloured brick and ornament, with fewer scenes of conquest.
Koldewey and the excavations
The German architect and archaeologist Robert Koldewey led the Deutsche Orient-Gesellschaft excavations at Babylon from 1899 until 1917. His training as an architect mattered. Mud-brick walls are hard to see in the ground because they have the same colour as the soil, and his careful methods for following their lines were an important development in archaeological methods in the region. His team uncovered the Ishtar Gate, the Processional Way, the palace area and the foundations of Etemenanki.
The German team shipped many glazed bricks to Berlin under the finds division of the time, and a section of the gate and street was reconstructed in the Pergamon Museum, opened around 1930. What visitors see in Berlin is therefore a reconstruction, built from recovered fragments. Some original foundation remains are still in Iraq. Later projects, including Iraqi restoration work in the late twentieth century, rebuilt parts of the site, and these reconstructions have been criticised because they cover original remains and mix modern and ancient brick.
Reading the evidence
Much of the work on Babylon was carried out more than a century ago, and records are incomplete. For that reason, dates for individual buildings and the details of how the decoration was arranged are sometimes uncertain, and scholars continue to reassess Koldewey’s conclusions using his notes and later fieldwork. Even so, the combination of ceremonial road, glazed brick and enormous walls remains one of the clearest examples of Mesopotamian monumental architecture.