Mantua is a city and comune in Lombardy. Mantua's historic power and influence under the Gonzaga family, made it one of the main artistic, cultural and notably musical hubs of Northern Italy and the country as a whole. Mantua is noted for its significant role in the history of opera and the city is known for its several architectural treasures and artifacts, elegant palaces or palazzi, and its medieval and Renaissance cityscape. It is the town to which Romeo was banished in William Shakespeare's play Romeo and Juliet. It is also the nearest town to the birthplace of the Roman writer, Virgil.
Mantua traces stem from the Roman period. It was renovated in the 15th and 16th centuries - including hydrological engineering, urban and architectural works. The participation of renowned architects like Leon Battista Alberti and Giulio Romano, and painters like Andrea Mantegna, makes Mantua a prominent capital of the Renaissance.
In 2007, Mantua's centro storico (old town) and Sabbioneta were declared by UNESCO to be a World Heritage Site.
References:The city walls of Avila were built in the 11th century to protect the citizens from the Moors. They have been well maintained throughout the centuries and are now a major tourist attraction as well as a UNESCO World Heritage Site. Visitors can walk around about half of the length of the walls.
The layout of the city is an even quadrilateral with a perimeter of 2,516 m. Its walls, which consist in part of stones already used in earlier constructions, have an average thickness of 3 m. Access to the city is afforded by nine gates of different periods; twin 20 m high towers, linked by a semi-circular arch, flank the oldest ones, Puerta de San Vicente and Puerta del Alcázar.