Көне Сейір тауы: Қызыл теңіз бен Ақаба шығанағы арасындағы аймақ

Mountainous region stretching between the Dead Sea and the Gulf of Aqaba

Mount Seir (הַר שֵׂעִיר) is the ancient and biblical name for a mountainous region stretching between the Dead Sea and the Gulf of Aqaba in the northwestern region of Edom and southeast of the Kingdom of Judah. It may also have marked the older historical limit of Ancient Egypt in Canaan. A place called "Seir, in the land of Shasu" (tꜣ šꜣsw sʿr – ta Shasu seʿer), thought to be near Petra, Jordan, is listed in the temple of Amenhotep III at Soleb (ca. 1380 BC). The Nabataean equivalent is šrʾ, and the modern Arabic equivalent is thought to be al Sharat (جبال الشراة) in Jordan.

The Hebrew Bible mentions two distinct geographical areas named Seir: a 'land of Seir' and 'Mount Seir' in the South, bordered by the Arabah to the west; and another 'Mount Seir' further north, on the north boundary of Judah, mentioned in the Book of Joshua .

Mount Seir was named for Seir the Horite, whose offspring, the Horites, had previously inhabited the area The children of Esau, the Edomites, battled against the Horites and destroyed them (Deuteronomy Deut 2:4 5, 12, 22 (1000)). Mount Seir is specifically noted as the place where Esau made his home (Genesis Genesis 32:3; 33:14, 16; 36:8 (1000); Joshua Joshua 24:4 (1000)). In the Book of Numbers, the prophet Balaam, predicting Israelite victories over the Trans Jordanian nations at the end of their Exodus from Egypt, stated "Edom shall be a possession; Seir also, his enemies, shall be a possession"
In the antique Song of Deborah in the Book of Judges, God is described as emerging from Seir to lead the Israelites in battle
Mount Seir is also given as the location where the remnants "of the Amalekites that had escaped" were annihilated by five hundred Simeonites (1 Chronicles 1 Chronicles 4:42 43 (1000)). In , the "inhabitants of Mt. Seir", i. e. the Edomites, came along with the Ammonites and Moabites against Jehoshaphat of Judah, however "the LORD set ambushments" against them, causing their forces to annihilate one another. Mount Seir is also referenced in the prophetic books as a term for Edom, as in Isaiah Isaiah 21:11 (1000) and Ezekiel Ezekiel 25:8 (1000) and Ezekiel 35:10 (1000).

There is also another Seir mountain near Hebron which, according to 15:10 (HE), was allotted to the tribe of Judah, near the modern town of Sa'ir in the West Bank of the Palestinian territories.

Before the emergence of the Israelite kingdoms and of Edom, with Mount Seir standing on the Edomite side of the border, this range marked the southeastern border of Egyptian Canaan (Late Bronze Age). This is suggested by the description of the military campaign undertaken in Canaan by Ramses III (r. 1186–1155 BCE), and possibly also by the Amarna letter EA 288, if "the land of Šeru" is to be understood to mean Seir.