The grotto of Santa Maria di Agnano opens on the slope of “monte” Risieddi, to the west of Ostuni, forming a large shelter under an overhang circa 10 m high. The cavity is almost horizontal as it goes back into the rock face, at between 169.50 and 173 m a.s.l. The complex is divided into three sectors, the interior, the shelter under the overhang and the exterior. The central part is dominated by the 17th century chapel which divides the great cavity into two areas, the west cavity and the east cavity. In 1882 C. De Giorgi noted the existence of a ruined altar and the remains of a fresco in the west cavity. At the beginning of the 1970 D. Coppola focused attention on the archaeological importance of the complex of S. Maria di Agnano. From the 21st April - 4th May 1987 D. Coppola, in collaboration with the Archaeological Superintendency for Apulia, dug a trial trench (8 x 3 m) which documented the existence of cult areas situated outside of the cavity itself, with the discovery of a 4th century B.C. hearth surrounded by votive offerings. Pottery fragments with dedicatory inscriptions and figured terracottas were also found. The first full excavation campaign in the grotto of Santa Maria di Agnano took place between the 16th September 1991-22nd February 1992. The excavations uncovered very important palaeolithic evidence. In the west cavity two burials of the Gravettian period (Ostuni 1 and 2) were excavated, the individuals having been buried in a fetal position. Ostuni 1, dated to 24.410 ± 320 B.P. (Gif 9247) on the basis of the charcoal found in the grave, was a pregnant woman with the remains of a fetus at an advanced stage of development. The burial Ostuni 2 was later although still of the Gravettian culture and was recently dated from a bone fragment to 23450+ 170 B.P. (ETH-24006). In the east cavity a 10 x 3 m trench was opened (divided into two sectors G, m 3 x 3 and E, m 7 x 3). The archaeological deposit reached a thickness of circa 3 m with stratified remains dating from from the medieval to Upper Palaeolithic periods. Outside the grotto the 2009 excavations documented the existence of an Epigravettian level (LTL2513A 17850 – 1770 cal BC.; LTL2786A 15255±65 -20.7±0.1 un-calibrated; LTL2514A 9700 – 9290 cal BC) followed by a collapse and an underlying Gravettian layer (LTL1811A 23945±110 -15.4±0.5), correlating with the burial Ostuni 1 in the interior. The extension of excavation in the external sanctuary area, with the collaboration of Martine Dewailly and Alessandro Quercia, exposed substantial remains of the Messapian sanctuary with in situ materials relating to cult rituals comprising local and imported pottery, Messapian inscriptions and bronzes. Numerous stone circles with votive pits and the remains of offerings, as well as the remains of a wall of squared limestone blocks were identified and will be excavated during 2010.

The 2015 excavations in the Archaeological and Nature Park of Santa Maria di Agnano concentrated on the stratigraphic analysis of the three investigated areas. The first zone was an area situated close to the western rock face, continuing the trench excavated in 2010-2011. The excavation of areas H-I-P-Q was extended with the aim of identifying the foundation of the limestone boulders forming the archaic-Classical _peribolos_ and intercepting levels that were not disturbed by the continual man-made modifications to the site. The archaeological stratigraphy in the south zone comprised various levels of agricultural soil and archaeological deposits dating to the Neolithic period. The Neolithic occupation surface presented hearths attested by various sized spreads of charcoal residue of difficult attribution. There was also a large hearth (Hearth1/Pit-Hearth1 bis) with a baked clay surface abutting the steep rock face delimiting the trench to the west. Nearby, Hearth 2 did not have a combustion structure of baked clay like the first, but was formed by a first level comprising a few fragments of Neolithic pottery and a base surface with outcrops of Pleistocene fauna and Epipalaeolithic-Mesolithic lithic industry. A small walled structured with a clear ritual function (Ritual Area 1) was situated up against the north side of the _peribolos_. It was lined with limestone slabs and flattened blocks and had two limestone altars preserved _in_ _situ_. Among the finds supporting the dating to between the 4th and 3rd centuries B.C. were a terracotta _protome_ with flowing hair and tall cap, a female divinity, probably Demeter, wearing a _pòlos_, and a miniature amphora. Another ritual area (Ritual Area 2) was identified to the east of Ritual Area 1. It was delimited by a semi-circular wall of limestone blocks. The finds included a fragmented _hydria_ painted with narrow red bands and decorated on the external surface of the vertical strap handle with the symbol of a “four-branched torch”, usually attributed to the cult of Demeter, and an iron lanceolate spearhead placed vertically and datable to the 4th century B.C. Further excavation took place on the lower terrace in front of the grotto (area M and L). In the southern extension of area M, large stones were uncovered situated at a higher level than the collapse investigated in 2011, from which they were separated by a layer of earth. This suggests the collapse occurred in two phases. A large quadrangular block with mouldings on the two visible sides, and a hole for the insertion of a cramp, which probably belonged to a large building, emerged from the south-western wall of area L. The excavation of the north-eastern corner of the area revealed a layer of friable yellow earth. This was crumbled local stone, called “tufina”, and could represent a surface whose alignment and size remain to be investigated. This season’s excavations showed the collapse to be more extensive, in particular area M towards the south and east. Towards the north, the collapse seemed to follow the line of a marked slope.

The continuation of excavations in area HP revealed a sequence of ill-defined Epipaleolithic-Mesolithic occupations followed by periodic, but not isolated episodes, represented by cult practices associated with the arrangement of stone circles and animal bones and several stones with linear incisions and more complex geometric decoration. A new trench was opened (Area R), in zone E of the sanctuary. Below the initial stratigraphy characterised by modern and medieval phases there was a chronologically sealed layer. A small Egnathian style cup and a Panathenaic type Apulian black-figure amphora were found within this layer. In the immediately underlying contexts, there were four empty stone circles and one still containing the offerings: a white-painted trilobed _oinochoe_ of Arpana production (4th-late 3rd century B.C.) and a black glaze _patera_, almost intact, containing a partially burnt astragalus, and an imported black bowl with random linear incisions on the surface. In addition to the pottery, numerous architectural fragments were recovered, among which a limestone element with a wave motif in low-relief. Associated with these elements, of particular interest were the fragments of a terracotta floor surface on which there were traces of _opus_ _signinum_ suggesting the existence of a vat. Lastly, numerous inscriptions were present on the pottery and for the first time on stone, including a fragment bearing a four-line inscription with six Greek letters and in the Messapian language (5th-4th century B.C.). South of area R, it was decided to open a new trench (area S). In the south-western part, a course of roughly-worked and squared stone blocks bonded with mortar on an E-W alignment was uncovered. Based on the pottery finds, this structure can be dated to a phase between the 12th and 14th century. In the eastern part of the trench, at c. 50 cm below ground level, a new course on a NE-SW alignment was exposed. Earlier than the first wall, it was built of large semi-worked limestone blocks and part of the later wall rested on top of it.

This season, the excavations at Santa Maria Agnano continued in last year’s areas and two new trenches were opened. The Holocene and Pleistocene levels underlying the rock face of the shelter in area H-P were explored, as were the sectors identified as “Scavo esterno”, relating to the Palaeo-Epipaleolithic stratigraphy, areas L-M on the lower terrace where Hellenistic layers are attested, and areas Re and T on the lower terrace and in the western cavity. This year, the brief excavation in area H-P revealed a sequence of ill-defined Epipalaeolithic-Mesolithic occupations followed by periodic, but not isolated episodes, represented by cult practices associated with the arrangement of stones with linear incisions. A new trench, Area Re, was opened in the eastern zone of the sanctuary. The removal of the humus revealed a pit (or cut) containing the burial of a dog (post-dating the 3rd century B.C.). The deposition was part of a ritual for the purification and sacralising of the area, as well as for protecting the underlying votive areas. The dog burial cut US 5006, an earlier occupation layer dated by pottery with painted bands and black glaze ware. A preliminary analysis of the forms of the plain ware pottery suggest parallels with 6th-3rd century B.C. types, a date that fits with the black glaze pottery and the ritual cooking wares relating to a final phase of use of the sacred area. The removal of the layer below the deposition revealed an unusual stratigraphic situation: a circle of stones (_bothros_) still containing the offering of a tall-footed black glaze kylix, a bronze coin from Arpi (of the bull/horse type) and a circular bronze pendent. Below a moderately compact layer of stones, new and substantial occupation evidence came to light, datable to the second half of the 4th century with layers rich in pottery and tile fragments. The layer, c. 25-30 cm deep, seemed to be a deliberate dump of votive and cult material from the sanctuary. The nature of this layer was confirmed by finds of a fragment of Messapian inscription on stone, of antefixes and bronze laminae. The subsequent layers showed a gradual, but clear decrease in the use of the area. It is probable that in the earliest phases (preceding the mid 4th century B.C.), this was a marginal area of the sanctuary. At depth of about 180 cm from ground level, an installation of large and medium sized represented the reorganisation of the area. The decision was made to open a new trench with the aim of understanding the occupation and votive dynamics inside the west grotto. Given the difficulty and delicate nature of the intervention, it was decided to prepare the area for future excavation, cleaning and laying out a trench of c. 3 x 4 m and only removing the first layer. A number of white-painted intact lamps (4th-3rd century B.C.) were found indicating the practice of nocturnal rituals relating to Chthonic divinities. A column fragment and a large stone block with moulding and decoration were also found, although their dating is uncertain.