Pollentia was founded by the consul Qintus Caecilius Metellus in 123 BC in the strategic location between the bays of Pollenca and Alcudia. It was the most important city in the Balearics duing the Roman period and covered an area of 15-20 hectares.
This area suffered a devastating fire in the 3rd century AD, but the city was not depopulated, since the construction of a fortification in the fifth century AD has been documented in the same forum. In the following centuries, the Pollentia site was partially or totally unpopulated, with the Christian medieval population settling down a bit further north, in the present town of Alcúdia. Excavations, since the 16th century, but especially since the beginning of the 20th century, have occurred mainly in the area of Sa Portella (a residential district), Camp d'en França (the city forum and the tabernae), and in the Roman theater.
There is also a museum, the Museu Monografic de Pollentia in the centre of Alcudia (by the church) which displays many of the objects found on the site.
References:The Walls of Constantinople are a series of defensive stone walls that have surrounded and protected the city of Constantinople (today Istanbul) since its founding as the new capital of the Roman Empire by Constantine the Great. With numerous additions and modifications during their history, they were the last great fortification system of antiquity, and one of the most complex and elaborate systems ever built. They were also the largest and strongest fortification in both the ancient and medieval world.
Initially built by Constantine the Great, the walls surrounded the new city on all sides, protecting it against attack from both sea and land. As the city grew, the famous double line of the Theodosian Walls was built in the 5th century. Although the other sections of the walls were less elaborate, they were, when well-manned, almost impregnable for any medieval besieger.