Glossary: A Question of Defense

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Glacis, Casemate Wall and Offset-Inset Wall

Glacis

The term “glacis” (gla-SEE), adopted from European military nomenclature, describes the massive earthen ramparts that surrounded virtually every important Canaanite city during the latter part of the Middle Bronze Age (c. 2000 to 1550 B.C.). This elaborate fortification system completely covered and reinforced the slopes of the mound on which the city was situated, hindering a direct enemy attack—by either assault troops or battering rams—against the main city wall on the summit.

Constructed of hard-packed layers of beaten earth, the glacis was often strengthened by a stone core or internal retaining walls, and was made even more formidable by a deep fosse, or dry moat, dug at its base. The steep slope of the glacis was usually covered with a layer of stone or a smooth plaster surface to prevent erosion and to make the enemy’s approach as difficult as possible. Although uniform in overall conception, each Canaanite city’s glacis was distinctive; each was suited to the city’s specific topographical situation and to the building materials at hand.

This method of fortification was apparently first utilized in Canaan in the MBA II A period (2000 to 1750 B.C.) as a response to the serious military threat posed by the increasing use of battering rams. Although scholars once believed that the glacis was introduced into Canaan by warlike invaders from the north, it is now generally seen as a local development in military architecture, made possible by the rise to power of a Canaanite elite who could mobilize the enormous labor force and material needed for the construction of such impressive defensive works.

In addition to providing military strength to the city’s inhabitants, the glacis, like other fortification walls used in the Bronze and Iron Ages, also had the advantage of conferring political prestige on the local ruler.

Casemate Wall

This term, also taken from European military nomenclature, describes a double, parallel line of fortification walls divided into internal chambers by regularly or irregularly spaced partition, or cross, walls. This was the common method of defense for cities and towns throughout Israel in the Iron Age, especially during the early part (in Biblical terms, the period of the Judges and of Kings David and Solomon, about 1200 to 928 B.C.).

Although similar double walls were also built in Canaan at the end of the Middle Bronze Age (16th century B.C.), the distinctive casemate walls of the Iron Age seem to have been related to architectural developments during the Israelite settlement period (1200–1000 B.C.). Recent excavations have shown that during the period of intensive Israelite settlement in the hill country of Canaan, the closely packed houses around the perimeter of unfortified villages were eventually used as an outer line of defense. By the time of the United Monarchy (c. 1020–920 B.C.), freestanding casemate walls had become a standard feature of Israelite military architecture. Fully 060developed examples from the time of the United Monarchy can be seen at Gezer (GEH-zer), Megiddo (mi-GEE-doe) and Hazor (hah-TSORE); at each of these royal cities, casemate walls were integrated into well-planned defensive systems, which included distinctive six-chambered “Solomonic” gates (three chambers on each side of the gateway).

Although casemate walls ceased to be the main form of urban fortification in Judah and Israel by the ninth century B.C., their utilitarian form—providing convenient storerooms and living quarters within the fortification walls—long continued to be used for the protection of citadels and isolated fortresses.

Offset-Inset Wall

Also called “salients and recesses,” this type of fortification wall replaced the casemate system, since it offered greater security against new methods of siege warfare—wheeled battering rams, scaling ladders, tunneling—introduced by the armies of the Assyrian empire. At the cities of Megiddo, Mizpeh (MEETS-peh) and Hazor—among others—the older casemate walls were filled and extended by the construction of a new type of solid wall, whose stone foundation, usually at least 10 feet thick, supported a superstructure of mudbrick.

Regularly spaced projecting “offsets,” or “salients,” in the wall’s foundation served as bases for bastions from which the city’s defenders could direct their arrows and slingstones—from two directions—against attacking troops. The earliest offset-inset walls at Megiddo and Hazor have been ascribed to the military preparations of King Ahab of Israel (871–852 B.C.); those at Mizpeh (Tell en-Nasbeh [tell en-NAHS-beh]) to King Asa of Judah (908–867 B.C.). Similar fortifications have been discovered at the Judean city of Lachish (la-KHEESH), conquered by the Assyrian king Sennacherib (seh-NAK-er-ib) in 701 B.C. Detailed depictions of the siege of Lachish, found on the walls of Sennacherib’s palace at Nineveh, have enabled archaeologists to accurately reconstruct the appearance of this impressive—yet ultimately doomed—fortification system.

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Glacis, Casemate Wall and Offset-Inset Wall Glacis The term “glacis” (gla-SEE), adopted from European military nomenclature, describes the massive earthen ramparts that surrounded virtually every important Canaanite city during the latter part of the Middle Bronze Age (c. 2000 to 1550 B.C.). This elaborate fortification system completely covered and reinforced the slopes of the mound on which the city was situated, hindering a direct enemy attack—by either assault troops or battering rams—against the main city wall on the summit. Constructed of hard-packed layers of beaten earth, the glacis was often strengthened by a stone core or internal retaining walls, […]