U+10C3B Old Turkic Letter Yenisei Ar

The Wikipedia has the following information about this codepoint:

The Old Turkic script (also known as variously Göktürk script, Orkhon script, Orkhon-Yenisey script, Turkic runes) was the alphabet used by the Göktürks and other early Turkic khanates from the 8th to 10th centuries to record the Old Turkic language.

The text is derived from the Aramaic alphabet.

The script is named after the Orkhon Valley in Mongolia where early 8th-century inscriptions were discovered in an 1889 expedition by Nikolai Yadrintsev. These Orkhon inscriptions were published by Vasily Radlov and deciphered by the Danish philologist Vilhelm Thomsen in 1893.

This writing system was later used within the Uyghur Khaganate. Additionally, a Yenisei variant is known from 9th-century Yenisei Kirghiz inscriptions, and it has likely cousins in the Talas Valley of Turkestan and the Old Hungarian alphabet of the 10th century. Words were usually written from right to left.