Every year hundreds of thousands of Muslims from around the world pour into Mecca making the Hajj pilgrimage. As one of the five pillars of Islam, the pilgrimage marks an important experience for many of the faith's adherent who are expected to visit the holy site as least once in their lives.
Although the requirements of Hajj have remained the same, Mecca itself has changed dramatically over the decades. Redevelopment of the site in 2013 lead authorities to remove a 17th century portico -- one of the oldest parts of Mecca's Grand Mosque -- in order to create more space for an ever-growing stream of pilgrims.
Many opposed the developments, however, saying they undermined the holy site's rich history and blaming the Saudi government for its oversight.
"I'm not against expanding the mosques at all, but there are ways you can go about it without destroying the historical aspects of these sites," Irfan Al Alawi, the executive director of the Islamic Heritage Research Foundation, told CNN. "Rather than engaging with heritage concerns, the Saudis are simply not interested."
Construction plans have revealed that further renovations may take place in the coming years, The Independent reports, raising concerns for Mecca's future.
Whether you support the renovations or not, Mecca's dramatic transformation is a thing to behold. Take a look at the these photos of the holy site from 1920-2013:
Before: 1920. After: 1988.
Before: 1979. After: 2001.
Before: 1935. After: 2013.
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Pilgrims in 1920 at the Kaaba, Mecca, Saudi Arabia, the most sacred site in the Islamic religion.
Mecca's great mosque, Mecca, Saudi Arabia, 1922.
Circa 1935: Aerial view of the Mecca with the porticoes which surround the Ka'bah.
The Kaaba in the centre of the Masjid al-Haram in Mecca, Saudi Arabia, March 21, 1967.
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The Kaaba in the centre of the Masjid al-Haram in Mecca, Saudi Arabia, circa 1979.
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A picture dated May 1988 shows Muslim pilgrims during the Hajj in Mecca.
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Aerial view of the holy Kaaba in the holy city of Mecca March 17, 2000.
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Hundreds of thousands of Muslim pilgrims throng Mecca's Grand Mosque, Islam's holiest shrine, late on Dec. 11, 2001, to mark the 27th night of the holy fasting month of Ramadan, known as Lailat al-Qadr.
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Muslims pray on Jan. 23, 2004, at the Grand Mosque in the holy city of Mecca ahead of the hajj, which begins on Jan. 30.
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Muslim pilgrims pray around the holist Al-Ka'aba mosque Jan. 14, 2005, in Mecca.
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An aerial view shows the Grand Mosque, Islam's holiest site, amid booming construction in the Saudi city of Mecca on Dec. 9, 2008.
A picture shows the Mecca Royal Clock Tower hotel complex, under construction in the holy Saudi city of Mecca on April 13, 2010.
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An aerial view shows Muslim pilgrims walking around the Kaaba in the Grand Mosque of the holy city of Mecca on Aug. 6, 2012.
The tallest clock tower in the world with the world's largest clock face at the Abraj Al-Bait Towers overlooks the Grand Mosque and its expansion in Mecca, Saudi Arabia, Wednesday, Oct. 16, 2013.