There are several versions related to the origin of the town's name. However, the most reliable one is that the name Deir Al-Ahmar is attributed to a big monastery in the area that was built with red stones. The town is characterized by its eight heritage churches as well as the center of the archbishopric of Ba'albeck-Deir Al-Ahmar.
The history of Deir Al-Ahmar is associated with the history of the Church of Saydet Al-Borj (Our Lady of the Tower), which has been re-built and became the Patron Saint of the village where she performed many miracles according to the residents. The town is also home to various vestiges, among which is the temple of Jupiter with its remaining two walls and big stones, whereas Saydet Al-Borj church was built over the demolished part.
Deir Al-Ahmar also includes Qasr Al-Banat (The girls' palace), a Roman palace that used to be inhabited by virgin girls, the column of Ia'at which was constructed in memory of the battles and old victories as well as the Roman road built during the Assyrian era, and that the Romans improved to become essential for the movement of their armies between Syria and the Mediterranean coast.