LONDON, Jan. 27 (UPI) -- Visitors to Britain's Royal Observatory will pay $16 beginning in March to stand with one foot in each of the eastern and western hemispheres, officials said.

Charging for entrance to the observatory's courtyard and its Prime Meridian line comes amid an increase of visitor numbers causing damage to the site, The Daily Telegraph reported Wednesday. Entrance to the courtyard, where the official dateline is marked, has been free since 2001, the newspaper said.

The admission fee will help fund work to combat wear and tear to the original home of international timekeeping while complying with health and safety laws, observatory officials said.

It is being initiated after a "prolonged period of limited investment" in the site, which is part of the National Maritime Museum, and will help develop new facilities, officials said.

Almost 1.6 million people visit the observatory in Greenwich in southeast London every year, four times as many as in 2001.

Children will still be admitted free, officials said, and the observatory's Astronomy Center and three interactive galleries will also remain free.

Experts call the site, designed by Sir Christopher Wren and built 330 years ago, one of the most important historic scientific sites in the world.