This is the perfect Algarve walk when it’s too nice to be indoors, but not warm enough to sit on a beach. Doesn’t that boardwalk call to you? It does to me.
Quinta de Marim is part of the Ria Formosa nature reserve. A 3 km trail leads through the pines and around the salt marshes, taking in the lovely old tidal mill en route. The main purpose of the reserve is conservation and education. The best option is to buy a map for a couple of euros and go at your own pace, but a guided tour is also available for advanced bookings.
I had never come across the concept of a tidal mill before and so was pleased that, inside the mill, display boards explain how it works.
In season I believe the mill operates a small cafe, but it was closed when I was there. The rest of the reserve incorporates salinas (or salt pans), a traditional farmhouse, a bird hospital and several hides for birdwatching. Traditionally Portuguese water poodles were kept here- a special breed with webbed toes, once used in the fishing process. These days they are most often seen in public demonstrations.
The reserve is close to Olhao Camping, and is signed off the E125 just before you reach Olhao, if you’re approaching from the east.