[1] It is a quadrangular masonry tower covered with white tiles, with blue horizontal stripes and a red lantern.

In the second half of the eighteenth century the fortress was the object of additional work, the most significant being that of 1762–1763, during which the parapet was widened, and that of 1793, in which battery spaces and quarters were expanded.

However, the strategic position its location had for military reasons also applied to navigation and it was decided to build a lighthouse on the site.

Between 1980 and 1981 work was carried out on the complete automation of the lighthouse, which was included in the telecontrol network of the approaches of the Port of Lisbon and in 2000 a new monitoring system was added.

[5] Throughout the twentieth century, the fort and lighthouse of Santa Marta gradually became degraded, leading to a proposal to revitalize the space.