The modern place name comes from the 12th century, probably due to some ancient walls of Roman origin found nearby.

However, in that same century, in 1706, the troops of King Philip V of Spain burnt down the parish church, and with it the town archive of Parets.

Parets del Vallès is in a good location, with excellent connections with the rest of Spain and Europe, hence it has attracted commerce and industry.

Most of those who work in Parets are employed by small or medium-sized companies, but major firms (for example Danone, Nutrexpa, Grupo Zeta, Fujifilm, Freudenberg, Grifols, Solvay, and Novartis) are represented.

Parets has an important forest and agricultural area shared among seven municipalities: Santa Maria de Gallecs.

Now, Gallecs has been officially recognised as an important nature reserve and several activities are undertaken to preserve it from the constant threat of building development.

It has a square base, a four-sided roof, and two round towers in the opposite angles of the building, with battlements and loopholes for weapons.