The old name of Tarshiha was "Alya." There are several accounts for why "Tarshiha" became the new name:
1- Some consider the name as a derivative of "Tor Eshaih," the name of nearby Mountain.
2- Some think it is derived from the name "Tair (BIRD) Al-Shaih," which is a white bird found in abundance in the area.
3- A third account derive the new name from a story of a poet who stopped at the village and drank water, then mentioned the word "Tarshiha" in his poem about the incident.
4- The fourth, and most common story. accounts the name to a leader called Shiha Jamal Ed-Dien who died while fighting the crusaders in the area. During the battle his head was severed and it flew, so people started crying "Tar (flew) Shiha" and the name was ultimately derived from it. Until 1948, his grave still existed in Tarshiha.
One of the most important historical buildings of Tarshiha re the castles. There are two castles that are to the vicinteis of Tarshiha: Al-Qareen Castle and Jedeen Castle.
1- Al-Qareen Castle: thought to have been built by the Knight Templers at the end of the 12th century. It was later captured by Al-Thaher, who destroyed parts of it. The Castle still exists facing the valley of Al-Qareen.
2- Jedeen Castle: lies 7 km to the south-west of Tarshiha. It was built by the Crusaders in the early 12th century. It was then captured, destroyed, and rebuilt, by the Muslims.
It was bought by the Jews from Adeeb Habaib (Lebanese) taking advantage of his financial troubles. They then took full control of it after the British mandate helped acquire it from the other owners and obstructed the people of Tarshiha from buying it back.Caves and Historic Artifacts:
As part of the land of Palestine, Tarshiha was full of historical caves, buildings or residential communities, artifacts, and castles.
Some of these caves are the caves of Al-Shiekh Al-Mujahed Mountain which contains the grave of Shiha Jamal Ed-Dein (which the town is believed to be named after him). Many ancient artifacts, antiques, and pottery have been found in these caves but where stolen by the British and the Israeli invaders.
Some of the old residential communities in Tarshiha are: Kherbat Alaya, Kherbat Al-Ruwesat, Kherbat Al-Mestah (Al-Regheb), Kherbat Um Al-Shaqef, and Kherbat Ja'athoon.