To cut down on litter and make an environmental statement, activists are trying to convince Independence National Historical Park to stop selling bottled water.

Caroline Wooten, an organizer with the group Corporate Accountability International, says the Grand Canyon National Park and 13 others across the country have stopped sales of bottled water. Instead, they're selling reusable bottles and installing stations offering free tap water.

"We're showing support to Superintendent Cynthia MacLeod, asking her to publicly endorse a bottled water-free policy here at Independence National Historic Park and throughout the national park system," Wooten said to a crowd of protesters.

Jane Cowley, spokeswoman for Independence National Park, says the park service is a conservation organization and is looking at all opportunities to be more sustainable.

As an urban park, the environmental situation in Philadelphia is not the same as at the Grand Canyon, she said.

"In order for any park to start the process of banning plastic bottles from the park, the first step is that the superintendent would have to initiate an analysis -- a fairly rigorous analysis in fact -- that would include things like weighing the pros and cons of banning plastic bottles, and looking at things like waste removal," Cowley said.

As for whether a bottled water ban would have much impact in an urban setting where visitors could walk around the corner to a convenience store, neither Cowley nor Wooten is addressing that now.