Most tourists to Istanbul inevitably make their way to its historic core along the Golden Horn, a peninsula rich in relics and monuments from the mighty Roman, Byzantine and Ottoman empires.

These days, the area is host to a modern-day battle over the expansion of a five-star hotel amid the ruins of an ancient palace.

The dispute pits government-backed developers of a site housing the luxury Four Seasons Hotel, occupying a converted, Ottoman-era prison, against critics who say work on a 60-room annex desecrate the remnants of a palace built by Constantine the Great in the fourth century.

"It is right on top of the most important remains in the ancient city of Constantinople," said Gunhan Danisman, a member of the Chamber of Architects of Turkey. He drew a comparison to show how"unthinkable" it is to embark on such a project: