The area where Cascais is located was already inhabited in the prehistoric era. The development of the zone has always been closely linked with that of Lisbon. The Celts, Iberians, Phonecians, Carthusians, Romans, Moors, and finally the Christians, all passed through here.

The city was reconquered from the Moors in 1153, although in its early history it came under the city of Cintra. It was classified as a municipality in 1364 at the orders of King Pedro I, and later King Juan II commissioned the construction of defense towers to avoid attacks from the sea. Portugal's first lighthouse was built in Cascais, and it was also the location of the first football match to be played in this country.

Cascais, along with the rest of the Portuguese coast, was unfortunately desolated by a violent earthquake on the 1st of November 1755, and a great part of the zone's heritage and patrimony was destroyed and lost, a great part of it disappearing forever.

In 1889, with the construction of the railway to Lisbon, the city entered a period of significant growth, leading it to be in the twentieth century one of the most important tourist destinations in the country, comparable to places such as Marbella, Montecarlo, Rimini.. and becoming an international tourism point of reference.

Cascais' tourism industry was born at the end of the nineteenth century, when the royalty chose the place as a holiday location. The main draw for tourists has always been the quality of its beaches. It soon became a fashionable spot for the elite of Portugal and the rest of Europe.