Taos Pueblo is made entirely of adobe — earth mixed with water and straw, then either poured into forms or made into sun-dried bricks. The walls are frequently several feet thick. The roofs of each of the five stories are supported by large timbers — vigas — hauled down from the mountain forests. Smaller pieces of wood — pine or aspen latillas — are placed side-by-side on top of the vigas; the whole roof is covered with packed dirt. The outside surfaces of the Pueblo are continuously maintained by replastering with think layers of mud. Interior walls are carefully coated with thin washes of white earth to keep them clean and bright. The Pueblo is actually many individual homes, built side-by-side and in layers, with common walls but no connecting doorways. In earlier days there were no doors or windows and entry was gained only from the top.