Cresmina Dune (Duna da Cresmina), Cascais

What makes this dune system particularly unique is the constant movement of sand particles due to prevailing northwest winds. As a result, the sand from Guincho and Cresmina beaches travels over the flat and rocky terrain of Cabo Raso before eventually returning to the sea near Guia, approximately 5 kilometers to the south.

The Guincho-Cresmina dunes are dynamic and constantly evolving due to the influence of strong winds. However, human interventions such as the construction of restaurants and hotels have hindered the natural movement of sand, leading to sediment deposits in areas further inland. This has resulted in a reduction in beach area and potential damage to nearby land and properties. To address these issues, the municipality of Cascais, in collaboration with the Portuguese Institute for Nature Conservation and Forests, has undertaken extensive rehabilitation efforts since 2011.

The primary objective of the rehabilitation work is to protect and preserve the dunes. Measures have been implemented to control pedestrian access and allow the local fauna and flora to recover from past disturbances caused by human activities, including dog walking, hiking, horse riding, and off-road vehicles. The dunes are now fully fenced, ensuring their undisturbed growth and development. Additionally, natural regenerators made of dead plant material have been strategically placed to mitigate wind speed and limit sand migration.

To enhance visitor understanding and appreciation of the Guincho-Cresmina dune system, the Cresmina Dune Interpretation Centre has been established. Informative panels located within a refreshment bar provide valuable information about the unique fauna and flora associated with the dunes. Wooden walkways have been constructed, spanning nearly 2 kilometers in length, to prevent unauthorized access to the sensitive dune ecosystem. These walkways offer visitors an opportunity to observe native plant species that are exclusive to the area and witness the delicate ecological balance between the dunes and their associated flora and fauna.

Efforts have also been made to restore the local vegetation. Invasive species like Carpobrotus edulis have been removed, and native plants such as European Marram Grass (Ammophila arenaria), Thrift (Armeria welwitschii), Beach Sabina (Juniperus turbinata), Sea Daffodil (Pancratium maritimum), and Ononis ramosissima have been reintroduced to promote ecological diversity and stability.

The Cresmina Dune is not only a captivating natural wonder but also a testament to the ongoing conservation and restoration efforts in the region. By protecting and rehabilitating this unique dune system, Cascais ensures the preservation of its natural heritage for future generations to appreciate and enjoy.