Archaeological survey was conducted by the authors (Khazaie, BahramiNia and Masjedi) in Kojour in the south of Caspian Sea and in Alborz Mountain in summer 2011. Kojourwas selected because of its suitable conditions for human occupation such as water sources, suitable soil, intermountain plains and finally its suitable elevation that protected this region from extensive environmental changes during prehistoric times such as glacial periods in high levels of Alborz Mountain as well as from Caspian Sea's water elevation changes. In our survey 47 archaeological sites were registered among which 10 sites had evidence from prehistoric times, 27 sites had evidence from historical times and 22 sites had evidence from Islamic times. Settlement pattern at the understudy area changed across the periods. Water sources and arable land with low slope and population were the most important factors of these changes.