The altar of Dionysus is a small excavation site showing the remains of a Dionysian temple from the 2nd Century BC. The Hellenistic altar has a pi-shaped design and features a flat access ramp on the fourth side instead of the usual staircase. On the perimeter wall was a frieze with a Dionysian theme.
The plane tree of Hippocrates is a famous oriental plane tree (Platanus orientalis) in the city of Kos, it is one of the most famous trees in the world. The tree is named after the ancient physician Hippocrates of Kos. According to legend, Hippocrates is said to have planted the tree and taught his pupils under the tree. If this was true, the tree would be older than 2400 years. Paul the Apostle is said to have preached under this tree some centuries later.
The Archaeological Site of Ancient Agora close to the port and right in the middle of Kos town is a large excavation area that is freely accessible. It is situated a bit below current street level between Eleftherías Square, Nafklirou Street, Platia Platanou (Platane Square with the Tree of Hippocrates and Loggia Mosque) and Leoforos Ippokratous Street. Visible are the remains of parts of ancient Agorá, its adjacent buildings and some beautiful mosaic floors.
Neratzia Fortress (Neratzia Castle), built by the knights of St John in the 14th century, is picturesquely located on a narrow peninsula east of the port of Kos town. The moat that built once at the north side of the castle to provide additional protection was later transformed into a beautiful palm tree boulevard. The only access to the fortress is an old stone bridge over this palm boulevard leading from the castle to the Plane Square (Platia Platanou) with the Tree of Hippocrates and the Loggia Mosque.
The Turkish bath (Hamam), to be more precise the old women's bath of Kos town is located behind the courthouse, at the passage to Platia Platanou (plane tree square) with the Tree of Hippocrates and the Loggia Mosque. The Haman was built in the 17th century, but severely damaged by the 1933 earthquake. It was rebuilt during Italian occupation, and operated until 1948 as a Turkish bath.
Casa Romana, the Roman house, is the reconstruction of a Roman villa on its original remains. The building, which is unremarkable from the outside, is located on the road Leoforos Grigoriou V in the immediate vicinity of the western excavation field and the Roman Odeon of Kos, opposite the Altar of Dionysus. The building stands on the site and on the original foundations of a Roman villa of the ancient city that belonged to a rich, aristocratic family.
Western Archaeological Zone is a somewhat uninspired name for a very interesting archaeological area of Kos Town which is freely accessible. It is situated opposite the ancient Roman Odeon and contains the remains of some of the most important monuments of ancient Kos.
The Odeon of Kos is one of the most important extant Roman buildings on Kos. Built in the 2nd century AD, it is preserved to this day in its basic features. The partially rebuilt 14 rows of seats give a good impression of the size of the originally covered building, the stage house is, however, preserved only in its foundations. Although the Odeon seems to be rather small, it could accommodate up to 750 people in ancient times.