Types and Contexts of Underground in Iranian Architecture and urbanism 

The basement is one of the most common spaces in most buildings that has been used since ancient times. Underground spaces have been used in past periods and traditional architecture and urban planning in various shapes, scales and contexts. Many of these spaces and their construction experiences are still in use.

The purpose of this article is to study the contexts, types and applications of underground spaces in the past and traditional Iranian architecture. In this regard, the most important question of this article is that "the necessities and types of underground spaces in architecture and what are the traditional urban planning of Iran? The research method used in this research is a historical-analytical research method with a qualitative and quantitative approach that is based on documentary study methods, library and case study.

Excavation of land, hills and mountains and sheltering in the basement, in addition to protecting users and their property, has created lasting spaces throughout history. These spaces are very attractive and memorable, especially for tourists and non-residents, due to their uniqueness in terms of external and internal form and landscape. Paying attention to the positive features of these spaces, especially in rural areas, can play an effective role in preserving their native identity.

The results indicate that the basement has been used in the past in various areas of housing, storage, shelter, animal care. Also, the reason for using these spaces is often security, climatic and environmental requirements, especially the steep slope of the land. The basement has a moderate air temperature due to its shelter in the heart of the earth in severe heat and cold, which is a great advantage for human use and its belongings in hot and humid, hot and dry (Shovadan in Dezful and Shoushtar city) and cold mountain climates. The basement has two main types of underground settlements and underground spaces. Underground settlements are also in two types of flat underground settlements such as Oei underground city and underground rock settlements such as Meimand. Underground spaces also have a variety of garden pit spaces, aqueducts, sheds, slums and storage.