Tuyserkan is a county located in the southwest foothills of Mount Alvand, and is a completely mountainous region. Its highest mountains are Alvand with an altitude of 3573 meters, Kūh-e Khān Gormaz with an altitude of 2868 meters, and Kamar Zard and Kalian, Siyah Darreh mountains with altitudes of 2168, 2582, and 2818 meters above sea level, respectively. The village of Karkhane in the southwest of the county, with an absolute elevation of 1555 meters, is considered the deepest part of the county.
Two rivers originate from the Tuyserkan region, as follows:
- The Karzan River originating from the upper parts of the Gashani and Sanjouzan valleys and springs; it extends to the southwestern part of the county to be called Ghelghelrud, after merging with the Sarabi and Serkan rivers near the village of Arikane.
- The Khorramrud River originating from the northeastern valleys of the county, springs up in the south of Mount Alvand, and after joining the Kondor River, flows westward.
The annual surface water discharge of this county is about 55 million cubic meters per year. In the past, there was an ancient city named Roudavar, with three quarters of Toi, Serkan, and Shekan. After the Mongol invasion, Roudavar lost its importance, and people turned to Tuy and subsequently, this area gradually became inhabited. The current Tuyserkan is a combination of two words, Tuy and Serkan, which is the old Tuy quarter. The Shekan quarter was destroyed in an earthquake, but Sarkan, which is located 10 kilometers northwest of Tuyserkan, still exists as one of the mountainous cities of the province.
The historical and cultural monuments of Tuyserkan County include the following:
- Tomb of Heyquq the Prophet
- The tomb of Mir Reza-od-Din Artimani
- Shah Abbasi Caravanserai in farasfaj
- Safavid Bridge of farasfaj
- Oshtoran Castle
- Qaleh Dokhtar in Shahrestaneh
- Sheikh Al-Khan Zangeneh Mosque and School
- Old Bazaar of Tuyserkan
- Chenar Mosque in Baghvar
- Zarhan Mausoleum
- Prince Naser's Palace
- Jama Mosque of Tuyserkan.
Tuyserkan County has a semi-arid and cold climate, and its rainfall regime is of the Mediterranean type, with an average annual rainfall of about 400 millimeters. The average annual temperature of this county is around 13-18 degrees Celsius.