Tubi Fittili refers to an ancient Roman masonry vaulting technique. The literal Latin translation means clay tube, and the process involves using clay bottles interlocked by mortar to form large-span arches. The technique provided an economic solution to many civic and infrastructural typologies in the Roman Empire due to its easy assembly without the use of complex wooden false work. This proved especially beneficial in regions of the empire where timber was extremely scarce. The inner and outer surface of the interlocking masonry units were often covered with mortar or finish plaster.