The AMI Prehistoric Collection was inaugurated in 1973 with a showing of the prehistoric holdings of the Palaeolithic, Neolithic, Bronze, and Iron Ages. Development of the collection, however, stretches back to 1902 and the find of a rich Iron Age necropolis at the Nesactium site—the discovery that prompted the founding of the museum.
The collection includes artefacts from the across Istria dated to the Palaeolithic, Mesolithic, Neolithic, Eneolithic, Bronze, and Iron Ages, and the study of the development of Istria's communities before the Roman invasion.
The core objective is to preserve and analyse Istria's prehistoric heritage, and its public-facing presentation. Years of systematic and continuing work aims to document the development of prehistoric communities through material remains such as tools, pottery, jewellery, and weapons. Specialist analysis is accompanied by collaborative efforts on numerous projects with a range of institutions and experts, both in Croatia and abroad, all aimed at advancing the study, protection, and presentation of our archaeological heritage.
The greatest abundance of Palaeolithic and Mesolithic finds were collected in the course of systematic and trial archaeological investigation at cave sites like Pupićina Cave, Vela Peć, and Vešanska Cave. Šandalja is one of the key sites; a flint chopper was recovered there estimated to be around 800,000 years old, making it one of the oldest objects made by humans in Europe. Romuald's Cave is another significant discovery, the site of the earliest known figural Palaeolithic paintings in the southeast of Europe.
The major Neolithic sites are Vižula near Medulin, Vela Gromača near Kavran, Kargadur, Sveti Mihovil, Ljubićeva Cave, and Laganiši.
Typical of the Bronze Age are artefacts collected from the many hillfort settlements, constituting a significant part of the collection. The major period sites are Monkodonja, Vrčin, Sveti Petar/ Tondolon, Gradac/Turan, Trogrla Cave, and Cingarela. The Vrčin, Mušego, and Maklavun sites stand out among the Bronze Age necropolises and tumuli.
The Iron Age is represented by finds from urnfield necropolises like those at Nesactium, Picugi, Pula, and Kaštel near Buje, while significant individual urn burials have been found at the Sveti Martin and Punta Kašteja sites. Notable finds include bronze situlae with figural decoration and imported pottery of South Italian and Greek origin, which testify to cultural exchange between Istria and the broader Mediterranean. Of particular value are the fragments of stone sculpture that bear witness to the unique Iron Age culture of the Histri, providing insight into their spiritual world and symbolism, and playing an important role in building the identity and cultural heritage of Istria.