JIDDA, Saudi Arabia  It is an architectural absurdity. Just south of the Grand Mosque in Mecca, the Muslim world’s holiest site, a kitsch rendition of London’s Big Ben is nearing completion. Called the Royal Mecca Clock Tower, it will be one of the tallest buildings in the world, the centerpiece of a complex that is housing a gargantuan shopping mall, an 800-room hotel and a prayer hall for several thousand people. Its muscular form, an unabashed knockoff of the original, blown up to a grotesque scale, will be decorated with Arabic inscriptions and topped by a crescent-shape spire in what feels like a cynical nod to Islam’s architectural past. To make room for it, the Saudi government bulldozed an 18th-century Ottoman fortress and the hill it stood on.

The tower is just one of many construction projects in the very center of Mecca, from train lines to numerous luxury high-rises and hotels and a huge expansion of the Grand Mosque. The historic core of Mecca is being reshaped in ways that many here find appalling, sparking unusually heated criticism of the authoritarian Saudi government.

“It is the commercialization of the house of God,” said Sami Angawi, a Saudi architect who founded a research center that studies urban planning issues surrounding the hajj, or pilgrimage to Mecca, and has been one of the development’s most vocal critics. “The closer to the mosque, the more expensive the apartments. In the most expensive towers, you can pay millions” for a 25-year leasing agreement, he said. “If you can see the mosque, you pay triple.”