the Abbas Abad region. The bridge is one of the masterpieces of the Danish engineering firm Kampsax, (consisting of Danish, German and Austrian engineers) serving the Trans-Iranian Railway network in Northern Iran. The construction of this bridge included craftsmen of many nationalities, including many Italian. The Master Carpenter for the construction of the lumber concrete forms was Giacomo Di Marco, from the Friuli region of Italy, and detailed in the book he authored. It has been said after finishing the bridge, people had a fear that the train wouldn't be able to pass the narrow bridge and that it would break. As a result, the engineer and his family stood under it when the first train passed the bridge (local accounts claim that Reza Shah had asked them to do so anyway). Lajim Tower Lajim Tower, also known as Tomb Tower of Lajim, is a tall cylindrical tower in the village of Lajim in the province of Mazandaran, Iran. The tower was built around AD 1022. The Lajim inscriptions includes the first documented example of the word qubba referring to the domed structure of the building. There is no doubt that the Lajim Tower was the mausoleum of an unknown Persian prince of Tabaristan. Kangelo Castle Kangelo Castle is a historical fortress located in the Savadkuh and in the village of Kangelo. The Kangelo Castle during the time The Sassanian Empire was built. According to historians, the castle of Kangelo was used as a place to worship the mirta. Espahbod Khorshid Cave This cave is located between the railway station of Pol-e-Sefid and Surkh Abad, in the vicinity of Do Ab. It was discovered in the year 1956. The cave has a simple area or hall, with a ceiling 80 m. in width and height, and is considered spectacular in the world. Near this cave is a remnant of a ruined castle and tower, which was once a beautiful structure of stone and mortar. This cave is also known as Dej-e-Afsanehie, and this was most probably the defense center of the House of Ispahbudhan of Mazandaran in the past. Balu Bridge Located along the Shirgah-Zirab road, near Talar river, it was made of fired bricks and mortar. The main part of this bridge was destroyed because of breaking, and now two herring-bone-shaped arches remained intact. One of them is wide and high, and another is wide and high. According to