Paço de Arcos (Portuguese pronunciation: [ˈpasu ˈdaɾkus] is a civil parish (Freguesias) in Oeiras, Portugal. With an area of 3,49 km², 28 000 inhabitants (2001) and population density of 3 390,5 hab/km². It was elevated to town by a decree at December 7, 1926.
Its name comes from the Palace of the Arches located at the entrance to the village (coming from Lisbon), where king D. Manuel I of Portugal watched Vasco da Gama's caravels leave for India. Nowadays, the Portuguese maritime academy - Escola Náutica Infante D. Henrique - is based there. It's also the base of the private business jet company NetJets Europe.
Paço de Arcos is where Quinta da Fonte is located , one of the biggest office parks in Europe, being the home of companies like General Electric, Nokia, Hewlett Packard, Intel, among others.