Great houses and towers differ from pueblos of the pure type but may
often be combined with them, forming composite houses arranged in
clusters called villages. Castles and towers may be isolated structures
without additional chambers, or may have many annexed rooms which
are rectangular, round, or semicircular in form. Semicircular towers
surrounded by concentric curved walls connected by radial partitions
forming compartments are shown in Horseshoe Ruin, to which attention
has been called in preceding pages, and possibly in the circular or
semicircular ruins on hilltops near Dolores.