This festival is exclusive to Aksum. There is much singing and dancing, celebrating the church of St. Maryam of Zion, in which the Ark of the Covenant is said to house in the oldest church found in the city of cradle of civilisation, Axum. 

Mariam Zion(Hidar Zion)- Celebration of Saint Mary of Axum is one of the main festivals celebrated in Axum. This festival is celebrated once a year to venerate St. Mary and especially to honor the believed existence of the Ark of the Covenant in St. Mary church of Axum. It is celebrated on November 30th (December 1st in a leap year), Hidar 21 according to the Ethiopian calendar. The celebration starts from the eve of the actual festival date.
St. Mary of Zion claims to contain the original Ark of the Covenant. Reportedly, the Ark was moved to the Chapel of the Tablet adjacent to the old church because a divine 'heat' from the Tablets had cracked the stones of its previous sanctum. Emperor Haile Selassie's wife, Empress Menen paid for the construction of the new chapel.
According to tradition, the Ark came to Ethiopia with Minilik I  after he visited his father King Solomon, whose mother was the Queen of Sheba. Only the guardian monk may view the Ark,in accordance with the Biblical accounts of the dangers of doing so for non-Kohanim. This lack of accessibility, and questions about the account as a whole, has led foreign scholars to express doubt about the veracity of the claim. The guardian monk is appointed for life by his predecessor before the predecessor dies. If the incumbent guardian dies without naming a successor, then the monks of the monastery hold an election to select the new guardian. The guardian then is confined to the chapel of the Ark of the Covenant for the rest of his life, praying before it and offering incense.