The Se of Lisbon was founded in 1147, immediately after Afonso Henriques took the city, on ground that had held the principal mosque. Its west front is unmistakable: two blunt towers flanking a rose window, a facade as much defensive as ecclesiastical, built at a time when the new kingdom's hold on the Tagus was far from secure. Successive centuries added a Gothic ambulatory and chapels, and successive earthquakes, above all that of 1755, brought down much of what they built. The restorations that followed, particularly those of the twentieth century, sought to return the building to its Romanesque austerity, which is why the interior today reads as sober and massive rather than ornate. Behind the church, excavations in the Gothic cloister have revealed Roman streets, Islamic housing and medieval structures superimposed on one another, an archaeological section through the history of Lisbon. The cathedral is thus both a monument and an open dig at the heart of the Alfama.
