At the Museum of Kaštela, visitors can explore the rich history and archaeology of the area—stories that are often invisible to those who wander through the city without historical context. The museum reveals the many traces of the past hidden beneath the earth and the sea, offering fascinating insights into this seemingly modern and industrial stretch of the Croatian coast.
The Trstenik site is located in the eastern part of the Bay of Kaštela, in Kaštel Sućurac. The oldest underwater finds in the bay were discovered off the coast of Resnik and can be linked to the most important Paleolithic site in this area — Mujina Cave. At the time the cave was in use, around 40,000 BC, the climate was significantly colder and sea levels were approximately 90 meters lower than today.
Today, the Bay of Kaštela is sheltered on the seaward side by the Split Peninsula to the east and Čiovo Island to the west. To the north lies Mount Kozjak, which protects the area from northern winds and continental climate influences. The mild climate allows for the cultivation of Mediterranean crops, primarily olive trees and grapevines, while the flysch soil enables the presence of surface water. At the site itself there is the Trstenik spring, after which the site was named.
During the period of Roman rule, the entire area surrounding the Bay of Kaštela formed part of the ager of the colony of Salona, which at its peak had around 60,000 inhabitants. The western entrance to Salona lies only 3 km from the site, and the Roman road Salona–Tragurium passed through the area. This road is still in use today and is known as the Roman Road. In its immediate vicinity ran the western Salonitan necropolis. Given its location and the presence of a plentiful water source, a Roman rural‑residential estate (villa rustica) was established in the Trstenik area.
The Trstenik area in Kaštel Sućurac has been known as an archaeological site since the early 20th century, when a pediment of a small temple dedicated to the god Silvanus was discovered. This pediment is now on display in the lapidarium of the Archaeological Museum in Split. Numerous Roman‑period finds, such as funerary urns and human remains, have been uncovered during construction works, and particularly interesting is the discovery of a lead pipe, indicating a high level of communal infrastructure. The Museum of the City of Kaštela conducted several land-based excavations, during which parts of the necropolis and architectural remains were identified and explored. During construction works related to the capture of the spring in 2022, a lid of a Roman sarcophagus was discovered, which had been reused as a watering trough for livestock.
The coastal position of the site is defined by an east–west oriented shoreline. In the site area, the coastline forms a small peninsula, and along the shore east of the stream, rocks shaped during the Roman period are still visible. The seabed in front of the stream’s mouth is covered by a thick layer of deposited silt, while most of the underwater area is overgrown with Posidonia seagrass. During the 20th century, like the entire Bay of Kaštela, Trstenik was exposed to environmental pollution as a result of intensive industrialization.
The underwater part of the site is considerably better known to the public, primarily due to the discovery of a series of exceptionally interesting and well-preserved archaeological finds. In 2002, following a report by a local diver, a large perforated dolium was recovered from the seabed at Trstenik. As a unique and complete example, it is now exhibited at the Croatian Maritime Museum in Split. Through continuous archaeological research led by Dr. Irena Radić Rossi of the University of Zadar, in cooperation with the Museum of the City of Kaštela and the ArsNautica Association, and with the support of the Croatian Ministry of Culture, Split-Dalmatia County, and the City of Kaštela, remains of the wooden structure of an ancient harbor, numerous Hispanic amphorae, and the remains of three Roman wooden ships have been discovered, in addition to the dolia.
The remains of the entire submerged ancient harbor are still visible today in aerial photographs and cover an area of approximately 2,500 m². The longer axis runs parallel to the coastline and extends for about 70 m, while the shorter axis, perpendicular to the shore, measures around 40 m. This was most likely a complexly constructed working quay belonging to a rural‑residential estate of the villa rustica type, with a developed commercial harbor located in close proximity to Salona.
Dressel 20 amphorae, discovered during the early research campaigns, are bordered by wooden piles and located in the central area south of the wooden harbor structures. A large number of examples are preserved intact and covered with protective netting, while several complete amphorae are on display at the Archbishop’s Palace in Kaštel Sućurac. These amphorae date to the 1st–2nd centuries AD and were used for the transport of olive oil. Due to their large volume, they were unsuitable for overland transport and were subsequently reused as fill for reinforcing the working quay.
The ship Trstenik 1 was discovered in 2006 while defining the western end of the working quay, at a depth of approximately 1.6 m. The vessel was deliberately sunk and filled with stones as part of the quay construction. It is about 12 m long and 4 m wide. According to radiocarbon (C14) analysis, the ship was likely built in the early 1st century AD. Its flat bottom and dense frame spacing indicate that it was a cargo vessel, designed for transporting heavy loads and maneuvering in the shallow coastal waters of the Bay of Kaštela. A rare intact find — a ceramic oil lamp — was discovered at the bow.
The ship Trstenik 2 was discovered in 2020 during the definition of the southwestern corner of the working quay. It is significantly smaller than Trstenik 1, measuring about 6 m in length and 2 m in width. The vessel belongs to the horeia type, characterized by a flat bow and pointed stern. It served for local use, functioning as a service boat within the harbor.
The ship Trstenik 3 was also discovered in 2020, sunk east of Trstenik 1. It measures approximately 9 m in length and 4 m in width. The frames are better preserved in the northern section, closer to the wooden quay structure. The vessel has been temporarily protected and is still under investigation.
