The handmade troglodytic architecture is a distinctive kind of architecture, which does not require major construction materials and consequently very low environmental load since its creation is majorly by extraction of space rather than addition of mass. The Architecture by subtraction rather than addition provides many opportunities which calls for comprehensive research and analysis. As there is no obligatory method in making spaces rather than material cohesion, there is no priority in constructing a troglodytic structure, either from the roof or from the floor. Dealing with stone blocks, rocks and piles of earth requires variety of tools as ax, hammer, chisel, and sledgehammer in order to shape the interior space.
In Iran, many magnificent cases of this architecture have taken place in different regions due to its various climates. This unique architecture is at odds with the conventional settlement patterns and construction methods and is always can take advantage of the mountains and valleys on the floor or wall, which is a good way to control climate fluctuation in different regions. Kandovan, Hilehvar in Azerbaijan, Meimand in Kerman, Karaftu Cave in Kurdistan, the troglodyte underground dwellings in Sāmen of Malayer, Arzanfoud in Hamadan, and underground complex at Noosh-Abād, Kāshan, are among notable and outstanding instances of known troglodytic architectures in Iran.
This study investigates key factors in the formation of handmade troglodytic architecture as well as their functional implication spatially. Another significant goal in this study is exploring main factors in categorizing handmade troglodytic architectures in Iran. It is mainly based on firsthand field activities and surveys, in which there were multiple visits to a large number of historical ruins and settlements in different parts of Iran. A number of archaeological excavations in different sites including troglodytic underground architectural dwellings at the abovementioned sites were closely examined for this study which were earlier supported via library and document investigations. The chronology and the activity system of these settlements as well as their functional implications found to be an integral touchstone. Due to their different structure, traits and exclusiveness compared to the usual archaeological monads, the methods for excavating troglodytic structures are different from conventional methods used to excavate other sites.
Based on the findings, creation of handmade troglodytic architectural sites depends on several factors including climatic and geographical conditions, defense, security, durability, and religion, which were deeply tied with the cultural, political, social and economic circumstances. This architecture can be classified in various formal types in terms of their external form, internal space, and function (religious, tombs, residential, and shelter).