The Syriac Sinaitic was discovered in Saint Catherine’s Monastary of Mount Sinai ( not the real Mt Sinai). This is also the place where the Codex Sinaiticus was discovered by Constantin von Tischendorf in a bin ready for the fire. A rubbish bin that is. (Codex Sinaiticus not the Syriac Sinaitic).
The Syriac Sinaitic being also discovered in Saint Catherine’s Monastary is a 4th to 5th century manuscript that has 358 pages of scripture. It contains the Gospels only. In 778 the manuscript was overwritten with a biography.