The A2 highway connects Lisbon to Albufeira, crossing the districts of Setúbal, Évora, Beja and Faro. The A2 is the second largest portuguese highway in extension, with a length of 240.2 km, and was projected to reach from Lisbon to resort areas on the southern coast. The completion of this highway occurred in 2002.
In 1997 the concession was granted to the Brisa company, who became responsible for the road construction and its layout design. Already this year, an opinion from the Instituto de Conservação da Natureza-ICN on prior provisional routes, concluded that for the Castro Verde Special Protection Area (SPA) the plana did not appear "technically satisfactory, or even feasible, to ensure birdlife conservation only by minimization measures".
The Environmental Impact Assessment-EIA and the committee for environmental impacts assessment imposed the condition of a new routing of the Aljustrel/Castro Verde section since the planned area was within a 10 km zone of the Castro Verde SPA. They also suggested an enlargement of the SPA in the south of Castro Verde to be preceded by a priority species study.
On January 19, 2000, the construction works were behind schedule and the pressure imposed by the mayors from the Association of Algarve-Amal Municipalities increased and the state secretary for the Environment issued an order to go ahead with the Aljustrel/Castro Verde route section, although conditioning it to strict compliance with the minimization and compensation measures mentioned by the EIA committee. One month later, the public consultation occurred for both EIAs related with the two last A2 route sections. For the environmental groups involved the compensation measures proposed for this section did not offer sufficient guarantees.
Thus the Grupo de Estudos de Ordenamento do Território e Ambiente-GEOTA, the environmental organization Quercus and the Liga para a Protecção da Natureza-LPN requested from the European Union-EU a deferral of the favorable decision on the EIA claiming that there were significant populations of several protected wild birds species inside Castro Verde SPA. Despite the EIA's negative findings and the existence of alternatives to the selected A2 route section, Portugal chose the route that most impacted an important Natura 2000 site. The A2 eventually open to traffic in July 2001. Simultaneously a process of infringement open by the EU Commission was already under way following the complaint presented by the environmental organizations. In 2004 the EU Commission brought an action of failure against the portuguese state before the European Court of Justice-ECJ.
In October 2006, the Court of Justice of the European Union-CJEU condemned Portugal for breach of the Birds and Habitats directives. The court found evidence that not only did the A2 route section imply significant environmental impacts; other possible alternatives were neglected and not included in the study. It was also determined that the construction of the road should be compensated by the Castro Verde SPA expansion. In early 2008, the EC announced a "final warning" to Portugal to take measures to mitigate the negative impacts on the two SPAs in the Alentejo region: Mourão/Moura/Barrancos and the Castro Verde. In February 2008 the legislation which extended these areas was approved by the Council of Ministers. The enlargement of the Castro Verde SPA involve 6,420 new hectares, spread across 2.034 ha in Almeirim and 4.386 ha Lombador/Figueirinha.