GPS:Lat.: 37° 57' 29.304" N Long.:8° 48' 33.5484" W

Sines is located in Portugal, Alentejo region (NUTII-PT18). The region is bounded north by the region of Lisbon, east by Andalusia and Extremadura (Spain), south by Algarve and west by the Atlantic sea. Sines is the most important urban center in Alentejo Litoral (Alentejo coast) region (NUTIII- PT181).

The main urban centres are Sines, Vila Nova de Santo André, Santiago do Cacém and Alcácer do Sal. At the southern limit of the Zils, at São Torpes beach, the begins Southwest Alentejo and Vicentine Coast Nature Park (Parque Natural do Sudoeste Alentejano e Costa Vicentina), whilst the Santo André and Sancha Lagoons Natural Reserve lies to the north and west (a Reserva Natural da Lagoa de Santo André e da Sancha). Zils is located in the triangle composed by Santiago do Cacém, Santo André and Sines.

Morphologically, the region of Sines has three different zones: the plains, the scarp and the residual volcanic massif relief. The north sandy coastline, Sines cape and rocky south coast by are also relevant. Most of the watercourse comes down the mountain range. Significant small rivers sculpt the valleys on the base, sometimes breaking the sedimentary cover, and run on the carbon schistose formations ( like Junqueira and Morgavel river)

On vegetation cover, human-induced forest prevails, mainly pine and eucalypt. Nowadays a significant part of the soils has been affected by forest crops.

The climate has a strong Mediterranean character moderated by Atlantic influence.