There are very few instances of party walls being utilised for two adjoining houses, though the buildings are often only a few inches apart. Even in the case of the round houses enclosed in square spaces and touching the square wall, the circular structure is quite complete at the point of contact. In one instance I measured a large walled parallelogram fronting on the principal causeway, seventeen yards in length, enclosing within it one square house of nine yards wide, and two circular houses, one on each side, the structures in each case being complete, but the circular walls in this instance merged for a few inches only at the point of contact with the square outer wall at the side. Whether these square or outer enclosures were tiled or were merely enclosed yards it is difficult to say, but that the houses themselves were so covered is evident from the immense number of well-made red shards scattered everywhere, and particularly inside the houses, the tiles being turned up at each end, so that a concave tile to cover over the joint between them would make a roof covered with them quite watertight. A door jamb and lintel in one house showed a well-carved rope moulding, but in most cases they were plain, the lintels and doorsteps containing, however, at the side a square-cut hollow, in which a block of wood was apparently inserted to receive the wooden peg or pivot which formed a sort of hinge for the door, an arrangement still adopted for the doors of barns, &c., in the neighbourhood; though Dr. Sarmento was of opinion that no wood was employed in the construction of the houses themselves, the polished rounded stones fixed to the walls in some of the houses, which Dr. Hübner considered to be bases of pillars, being in the opinion of the Portuguese archæologist seats for the inhabitants.
The round houses are usually about fourteen feet in diameter, and the walls remaining rarely rise above four or five feet from the surface. The doorstep is usually raised a foot or so above the level of the ground. One round house has been tentatively rebuilt by Dr. Sarmento on the level space on the top of the hill, an unattractive beehive-looking structure without windows, but later investigation convinced him that he had built it too high; and that it should not be of so great an elevation as the measure of its diameter. The principal thoroughfares running transversely on the slope of the hill are carefully walled upon the scarped inner side, and in some cases the stone water channel runs alongside of it.