Terrace Temple
With the help of an excellent map I found on the web (and my GPS-information of the pictures) I identify this as the Terrace temple.
From the Wikipedia: [Six temples have been excavated, two of Hellenistic and four of Roman origin.} Probably the terrace temple of the 3rd century BC facing a circle of columns has the greatest appeal. Inside the circle an obelisk has been found, which is also depicted on old Kaunian coins. The obelisk was the symbol of king Kaunos, who according to mythology established the ancient city bearing his name.