Mecca kilometer elevated metro transports pilgrims to holy sites Mount Arafat, Muzdalifah and Mina in the city during hajj reducing the congestion on the roads. Mecca Metro, officially known as Makkah Mass Rail Transit, is a planned four-line metro system for the city. This will be in addition to the Al Mashaaer Al Mugaddassah Metro which carries pilgrims during Hajj. A high speed inter-city rail line (Haramain High Speed Rail Project also known as the "Western Railway"), is under construction in Saudi Arabia. It will link along 444 kilometres (276 mi), the Muslim holy cities of Medina and Mecca via King
Mecca squares. Traditional homes are built of local rock and are generally two to three stories. The total area of Mecca today is over . In pre-modern Mecca, the city used a few chief sources of water. The first were local wells, such as the Zamzam Well, that produced generally brackish water. The second source was the spring of Ayn Zubayda. The sources of this spring are the mountains of J̲abal Saʿd (Jabal Sa'd) and Jabal Kabkāb, which are a few kilometers east of Jabal Arafa or about southeast of Mecca. Water was transported from it using underground channels. A very