After eight years' of major construction, the Forbidden City has opened around half of its area to visitors, the administrative office of the Palace Museum announced Tuesday.

The renovation project that began in 2002, has added three hectares of visiting area, about 4 percent of the total, to the Forbidden City. Forty-six percent of the total area is now open to the public, but the speed of expansion cannot keep up with the ever-growing flow of visitors, according to the Palace Museum, administrator of the Forbidden City.

Visitors to the ancient structure have increased by 66 percent from 2002's 7.1 million to 2009's 11.9 million.

"The opened area in the Forbidden City has an ideal capacity to accommodate 30,000 visitors each day, but in busy seasons, the number can hit 130,000," Shan Jixiang, head of the State Administration of Cultural Heritage, said at a conference last week. "The expansion of the tourist area could greatly reduce this pressure and reduce the possibility of relics and sites being damaged."

As repair work continues, the Forbidden City will open more of its royal sites that have not been accessible to the public since it opened to visitors in 1925.

There are more than 9,000 rooms in the Forbidden City, with tourists mainly allowed to enter those located along the central axes of the area. Many of the courtyards on both sides of the axes are not yet open to visitors, which is the main target of the renovation, according to the museum.

Before the renovation, 9 percent of all buildings in the Forbidden City were occupied by outside institutions with many of them relocated to make room for tourism expansion.

Several research institutes and offices in the east and west sections will also be relocated to the west corner of the Forbidden City to make more room for tourists, according to Shan.

The renovated project is scheduled for completion in 2020 when 76 percent of the Forbidden City is expected to be open to the public. Admission ticket prices will remain the same, Shan added.