With the increase of gry land, of better security conditions, demographic increase and the progressive economic development linked to the maritime activity, there was the expansion of the village outside the medieval walled enclosure.
From this expansion and during the Restoration Wars in 1640 resulted in the construction of the Fort of São Sebastião on Cerro do Cabeço and the Revelim of Santo António on the hill called Rocha do Zambujal, which involves the said Santo António Hermitage, erected by D. João IV.
These two fortified zones annexed to the Castle made this village in the XVI / XVII century, the most important place of war in the Algarve.
The Revelim de Santo António is composed of a structure upholstered in "U", holding in its center and top of the hill the Hermitage of the same name with the location W / E, functioning as a viewpoint on the two elements that enrich it visually, Rio Guadiana and the Sapal de Castro Marim.
This Hermitage had, during its construction, a quadrangular plant having, over time, undergone extensions.
It is currently composed by longitudinal plan, enlarged N. by volume of the sacristy and arrumos room and the S. by multipurpose room. With a high Main Facade, to W., and with a walled enclosure, composed of: a wooden portal enveloped in a frame of stone flanked by lambrim and gray-painted wedges, surmounted by a border that rests laterally on two painted scrolls; under quadrangular window with frame in stone finished by border, with motives equal to that of the portal; two-roofed cross with Christ's cross to the center; flanked by side belfry.
Lateral facade N. blind composed by two-sided steeple topped by cornice, topped by two boquilla pinnacles, and by volume of the sacristy and arrumos room with roof cover of a water and double eaves.
Lateral Façade S. Blind composed by volume of polyvalent room with entrance to S., with a water cover and double-edged finish.
Facade W, corresponding to the volume of the main chapel, surrounded to S. by the polyvalent hall and N. by the volume of the sacristy, this one with window to W .; with dome cover and two-sided roof with double-edged finish.
Interior composed of longitudinal nave, with roof in crib vault; two lateral altarpieces from the middle of the eighteenth century, dedicated to Our Lady of Conception and St. Elizabeth, ripped in the side arches with a perfect round arch on polychrome wooden tables and altar tables surrounded by composition of scrolls in painted carving and central coat of arms.
On the side of the Gospel, polychrome wood quadrangular pulpit, with access by single door; marbled painted wooden skirting board; on it are distributed, on both sides, seven tablets of painting, with scenes of the life of the oracle, inserted in back of painted wood with vegetalista decoration and cornice of auction.
Perfect triumphal arch over painted imposing; access to the main chapel by a single step; crib vault cover with painted caissons; altarpiece of the eighteenth century, plan of five panels defined by pseudo-Solomonic columns to which architrave overlays and central edicule with image of St. Anthony; laterally two small images under plinths; topped with scrollwork decorations; laterally two paintings of scenes from the life of the oracle and two access doors, the one from the left to the sacristy, the one from the right to the multipurpose room. Sacristy composed by W. window and small arcaz in wood.