Question: What country located within the city of Rome,is hime to a flight of steps built by Antonio da Sangallo the Younger in the early 16th century?
Related documents: [0]  [DOC] Scala Regia (] and ] ; English: Royal Staircase ) is a flight of steps in the Vatican City and is part of the formal entrance to the Vatican. It was built by Antonio da Sangallo the Younger in the early 16th century, to connect the Apostolic Palace to St. Peter's Basilica, and restored by Gian Lorenzo Bernini from 1663 to 1666. [END] 
[1]  [DOC] Vatican City ( ; Italian: "Città del Vaticano" ] ; Latin: "Civitas Vaticana" ), officially Vatican City State or the State of Vatican City (Italian: "Stato della Città del Vaticano" ; Latin: "Status Civitatis Vaticanae" ), is a country located within the city of Rome. With an area of approximately 44 hectares (110 acres), and a population of 1,000, it is the smallest country in the world by both area and population. However, formally it is not sovereign, with sovereignty being held by the Holy See. [END] 
Answer: 
Vatican City
Vatican City