Its name originates from the medieval "Via Regia", traced along the coast and it began to gain importance, after that the inhabitants of Lucca decided to set here their sea port.
In 1334 a fortress was built here to defend the settlement from the pirate raids.In 1463 the works for the drainage of the hinterland began.

In 1548 Viareggio became the seat of a commissariat and in 1617 chief town of vicariate. The land was a long time inhabited owing to the malaria, which was once widespread. Thanks to the drainage works, planned by Zendrini and begun in 1740 and to the intervention of Maria Luisa di Borbone, Viareggio gained a large part of its bloom.
In the town centre there is the Tower Matilda, a fifteenth-century fortification, built here by the government of Lucca to defend warehouses and the whole suburb. After the end of the construction works (1542) a palace for the commissariat of coast defence was built near the tower. In the 17th century the tower, today used for art exhibitions, was added a storey, demolished in 1947

Also Forte dei Marmi, famous for its bathing establishments and its centre, is a symbol of Versilia.

Noteworthy are the promenade near the sea-shore (called "Pontile") and the Fortress, ordered by Pietro Leopoldo, Grand-duke of Tuscany, in defence of the coast to be built.
The fortress, used to accommodate soldiers and equipped with efficient cannons, became an important shelter from the pirate raids.
Leopoldo I wanted to protect also the lands in the hinterland to increase the settlement of a population of fishers, seamen, porters and farmers.
Many changes were introduced to the original set-up of Forte dei Marmi, except for the bulwark, which still dominates the sea.