Although first noted by explorers in the mid-19th century CE, and subsequently briefly excavated in 1899 by the British archaeologists F.J. Bliss and R.A.S. Macalister, extensive exploration of the site was not conducted until 1996, when a long-term project was commenced at the site, directed by Aren Maeir of Bar-Ilan University, Israel. Since 1996, excavations, surveys and other studies have been conducted at the site, focusing on various cultures, periods and aspects relating to the site, its culture and history, and its surroundings.
The site was inhabited from Proto-Historic through Modern times. The earliest evidence for settlement is from the Chalcolithic Period (ca. 5th mill. BCE), after which there is continuous occupation until the modern Palestinian village of Tell es-Safi, abandoned in 1948 during Israel's War of Independence.
During the Early Bronze Age there is evidence of a large urban site, apparently similar to other EB III urban sites in southern Canaan, such as nearby Tel Yarmut.
Scant evidence of this period was found on the tell in the form of stray sherds. In the vicinity of the tell (to the east, in Area C6) evidence of tombs and possible domestic activities were found.
Finds from the MB IIB (and a few MB IIA) were found on various parts of the tell in the survey (including a scarab of Khyan, found in the 1960s). Recently, in the 2006 season, evidence of an impressive MB IIB fortification was found in the vicinity of the summit of the tell, comprising a stone wall/tower and a packed earth rampart/glacis.
The Late Bronze remains at the site are impressive as well, evidence of the Canaanite city of Gath, which is mentioned in the El-Amarna letters. Finds from this period include a large, apparently public building, cultic-related finds, and a small collection of Egyptiaca, including two Egyptian Hieratic inscriptions, both inscribed on locally-made vessels. This city was apparently destroyed at the end of the Late Bronze Age, most probably with the arrival of the Philistines.
During the Iron Age, the site becomes a major Philistine site, "Gath of the Philistines," one of the five cities of the Philistine "Pentapolis," known from biblical and extra-biblical sources. Settled from the earliest phases of the Philistine culture (ca. 1175 BCE), evidence of the various stages of the Philistine culture have been found. In particular, finds indicating the gradual transformation of the Philistines, from a non-local (Aegaean) culture, to a more locally-oriented culture abound. This process, which has been termed "Acculturation" or "Creolization" can be seen in various aspects of the Philistine culture, as the Iron Age unfolds.
Of particular importance are the strata dating to the 10th-9th cent. BCE, in which rich assemblages of finds were uncovered. These strata enable the study of the entire sequence of the Philistine culture, since at other Philistine sites (such as Ekron, Ashdod, and Ashkelon) these phases are not well-represented.
A very impressive, site-wide destruction is evidenced at the site during the late Iron Age IIA (ca. late 9th cent. BCE). Throughout the site there is evidence of this destruction, and well-preserved assemblages of finds. The dating of this destruction to the late 9th cent. BCE is a strong indication that it can be related to the conquest of Gath by Hazael, King of Aram Damascus, as mentioned in II Kings 12:18. Evidence of a large-scale siege system that was found surrounding the site, is apparently related to this event. This siege system, which comprises a man-made siege trench, a related berm (earth embankment) and other elements, is currently the earliest archaeological evidence "on the ground" for an ancient siege system.
Among the numerous finds from this destruction level, one can note the impressive pottery assemblage, various cultic objects, a bone tool workshop, and assorted other finds.
In the 2005 season, below the late 9th cent. BCE destruction level, in a stratum dating to an earlier phase of the Iron Age IIA, an important inscription was found. Scratched on a sherd typical of the Iron Age IIA, two non-Semitic names written in Semitic "Proto-Canaanite" letters were found. These two names "ALWT" (אלות) and "WLT" (ולת) are etymologically somewhat similar to the name Goliath (גלית), the well-known Philistine champion, who according to the biblical text originated from Gath.
These two names indicate that names similar to the name Goliath were in use in Philistia during the Iron Age IIA, at just about the same time as Goliath is described in the Bible. Although not a proof of the existence of Goliath, it does provide nice evidence of the cultural milieu of this period. In any case, they provide a useful example of the names used by the Philistines during that time, and the earliest evidence for the use of an alphabetic writing system in the Philistine culture.
Following the destruction of the site by Hazael, Philistine Gath loses its role as a primary Philistine city. Although the site is settled during later periods, it never regains its role as a site of central importance. During the Crusader period, following the conquest of the land during the 1st Crusade, a small fortress, "Blanche Garde", is built at the site, as part of the Crusader encirclement of Fatimid Ashkelon. This site was subsequently captured by the Ayyubids, and served the basis for the Medieval and Modern village of Tell es-Safi, which existed until 1948. The ruins of the castle and the village can be seen on the site today. Portions of the exterior fortifications of the castle have been excavated in recent years.