al-Masa'a (المسعى) is a path between the hills of Safa and Marwah, where according to Islamic tradition Hagar (Hajarah) travelled back and forth seven times in search of water or help for her infant son Ishmael. Today the walkway is entirely covered by a gallery and is divided into four one-way lanes, of which the inner two are reserved for the elderly and disabled.
circa 2000 CE
General view of Sa'i gallery as seen from the Safa, the point where the pilgrims start the Sa'i, moving towards Jabl Marwah. The two points and the path between al-Safa and al-Marwah are now inside a long gallery that forms part of the Masjid al-Haram. The distance between Safa and Marwa is approximately 450 meter (1,480 feet), so that seven trips back and forth amount to roughly 3.2 km (2.0 miles).
circa 140 CE
The Swiss traveller Burckhardt gives an account of the al-Masa'a when he came to Mecca in the year 1814 CE. He describes it as a flat street some 600 meters in length (actual length is some 450 meters), with shops and cafes on both sides. He expalains that the al-Masa'a street is one of the most prestegious street. Burckhardt's account notes that the street was covered with an arched roof, built during the Ottoman era, in the style of a Sooq.
circa 1960 CE
During the First Saudi expansion of Masjid al-Haram the Mas'a gallery (and the hills of as-Safa and al-Marwah) is included in the Mosque, via roofing and enclosures.