concave-convex segments, an urbanism of Baroque and Rococo decorative forms. The staircase was decorated between 1800 and 1805 by 12 large soapstone statues of Old Testament prophets, by Aleijadinho and his officers. The 6 chapels located in the first part of the sanctuary, square in plan, were also decorated with sculptural sets by Aleijadinho. The landscape set formed by the church, the churchyard with prophets and chapels is of great expressiveness, unparalleled in the colony. Military architecture In the early years of colonization one of the biggest concerns of the Portuguese metropolis was to secure the possession of the territory, and the first settlements were always fortified with palisaded walls and forts. The oldest fortress still standing in Brazil is São Tiago Fort (which still survives under the name São João da Bertioga Fort), in Bertioga, dating from 1532. It was at first a wooden palisade, and was later remodeled in masonry, acquiring its current configuration. Later a series of other forts were erected all along the coast, and at some points in the countryside, and they basically followed the same model that remained without much variation over the centuries, of square or polygonal plan, sometimes deformed to fit the underlying topography. They had a chamfered base in bare stone, whitewashed masonry walls on top, with guardhouses interspersed, and a series of stripped dwellings inside, often with some chapel or small temple. Occasionally more or less elaborate portals were erected at the entrance of the fortresses, following the late Renaissance or Mannerist style, which predominated during the 16th and 17th centuries. An original example is São Marcelo Fort, built on an islet in Salvador in the 1650s and the only one of circular plan in Brazil. Civil architecture Typology In terms of volumetric typology, the main categories of civilian colonial buildings are shed-roofed (ranches, kitchens), gable-roofed (very common in cities), hip-roofed (larger buildings such as pavilions, townhouses, public facilities), and cloisters (ditto). An intermediate solution between the last two categories were the "L-shaped" plans. With respect to the simpler rural constructions (designated as "sertanejo" or "caboclo" houses, "mocambos", "palhoças", etc.), for free men, they generally had a vegetal covering of straw and walls of wattle and daub. They had a single room and a front veranda. On the largest rural properties, the plantations, there were three main elements: the senzala, the mill and the big house. The senzalas had a