There is a number of places to go swimming in the sea in the area, depending on preferences and weather.

From Olhão: From here you can catch a boat to Armona, which offers a few facilities.

ferry
Fuzeta: There is a quite protected, sandy beach at Fuzeta itself, with cafes and ice cream sale. Alternatively, catch a boat to Ilha de Fuzeta (actually it is the eastern en of Ilha de Armona) where there are a few cafes. For less crowds, turn left (east) when you have walked across the island from the ferry landing.

To get to Fuzeta from Casa Flor de Sal:
From the gate, turn right.
At the T-junction where all the mailboxes are, turn right.
Follow this road for the next few km, take your time as it is a bit narrow and has a lot of twists and turns.
At another T-junction (other traffic has priority), turn right again.
You soon arrive in Fuzeta, follow the road which includes a sharp turn just after crossing a bridge over the railvay line.
Near the beach and ferries, there is a parking area.


Ria Formosa at Casa Flor de Sal: You can also go walking to the Ria just in front of the house, swimming can be 15 minutes walk away in reasonable gentle pace.

Leave Casa Flor de Sal, turn left down the road.
After 50 metres, turn left down the dirt road past a few houses.
Cross the railway line with care, listen AND look as it can be hard to hear the trains depending on the wind.
Go along the unused salt pans on the dirt road.
Where the road turns sharp to the left, continue straight on and cross where the water reaches at high tide.

RiaPath1
At this point there is no obvious path, but continue in the same direction and a path reappears.
Follow this path until you cone to a suitable point to enter the tidal canal.
The canal has muddy sides but sandy bottom and is fine for swimming, in particular in the hours after high tide.

RiaPath2
If you want to cross to Ilha de Armona (the barrier island, follow the canal until it ends in a large canal which is between you and the island. At low tide, there is about 20-30 meters to swim across.

The best footwear for this option is trekking sandals or similar open footwear that tolerates water