Kavala is northeast from Thessaloniki, on a more scenic route than the truck-congested motorway.
Kavala is the newer name for Philippi, the city where the apostle Paul is supposed to have first landed. Its aqueduct here is not Roman, but dates from the time of Suleiman the Magnificent, constructed 1520-1530 or so. That little sign on the left that you can barely see, says that Constantinople is 480 Km away (take 2/3 of that for miles, approximately. So, 250 +/- miles?). Kavala was part of the Ottoman Empire from 1371-1912. See http://www.citizendia.org/Kavala
Kavala, Castle, Greece.
The castle at Kavala was begun in in the 5th century BC, with Byzantine additions. See http://www.superbgreece.com/Makedonia/Kavala/index.