Oeiras is a town and municipality located between the municipalities of Lisbon and Cascais.
It is on Estoril coast, but still on the shores of the Tagus river. The Tagus river ends in Oeiras.
The current statistics of Portugal put this municipality as having the highest income per capita of Portugal. The reason for that is that it tends to attract many companies headquarters located in the region of Lisbon. It is also a favourite location for skilled workers and foreign expats to live.
However, tourists cross this area by train, between the stations of Algés and Oeiras, on the way to Estoril or Cascais and rarely visit it. Some beaches located closer to Lisbon are poluted (Algés, Paço de Arcos) but the one at Santo Amaro de Oeiras, right where the Tagus meet the Atlantic is ok.
The towns of Paço de Arcos, Caxias, Cruz Quebrada and Algés, in Oeiras municipality are worth to visit.