The castle is located on Rudbar Shahrestan, north-east of Razmian village. It is one of the most important castle in Esma'ilie on Saljughi era. The date of it's building isn't clear. The castle became well-known on Esma'ilie era because of its special position. It was considered an important castle after Alamut castle.
Lambeser castle is on top of a vast and flat mountain. It is seprate from other mountains by being of surrounding rivers on west, east and south foothills.
It's dimensions are 480m on north-south side and 190m on east-west side. There is an enormous wall in height 10m and now some parts of it remained. It's water is applied from Nine rood that it's distance is two farsang and it is reserved on some water reservoirs. Iran's cultural heritage organization is doing scientific digging in the area.