A harbor from the Hellenistic period was found at Akko on the Mediterranean coast. Here is a brief description of the discovery provided by the Israel Antiquities Authority.
The part of the floor that has been revealed so far extends for a distance of 15 meters and is 4 meters wide (the full dimensions of the floor have not yet been exposed). The floor was built of rectangular, smoothly dressed kurkar stones that were placed atop a foundation course of roughly hewn kurkar stones arranged next to each other as “headers”. In probes that were conducted beneath the floor, numerous fragments of ceramic jars of Aegean provenance (from Rhodes, Kos and elsewhere) were found that were used to transport wine, as well as tableware and cooking vessels. Among the other artifacts recovered were a Greek style bronze arrowhead and bronze coins that are covered with marine encrustations. A preliminary identification of the finds shows that the floor was constructed in the Hellenistic period (end of the third century until the middle of the second century BCE) as part of a national project.
The photo below shows some of the kurkar stone pavement discovered one meter under the present water level.
Akko (Acre or Accho) is mentioned in Judges 1:31 as a city of the tribe of Asher. During the late 3rd or early 2nd century B.C. Akko was given the name Ptolemais by Ptolemy I or II of Egypt. Ptolemais is the name we read in the New Testament. Paul and his companions stopped at Ptolemais for one day on the return from his third journey in the Greco-Roman world.
When we had finished the voyage from Tyre, we arrived at Ptolemais, and we greeted the brothers and stayed with them for one day. (Acts 21:7 ESV)
Several things are learned from this text (and context). The previous stop was a few miles north at Tyre where they had stayed for seven days (Acts 21:4-6). After Ptolemais they arrived at Caesarea.
Paul’s companions included all of those “messengers” of the churches who were taking the contributions of the churches of Macedonia and Achaia to the poor among the saints at Jerusalem (Romans 15:25-27; 2 Corinthians 8-9). A list of names is given in Acts 20:4.