Rob Stuart, 49, Phila. activist

Robert Andrew Stuart, who helped win broader public access to Schuylkill River Park, fought against illegal guns, and led efforts to improve his Logan Square neighborhood and the city, died suddenly Wednesday of a heart attack. He was 49.

Mr. Stuart, who from 2006 to 2009 was president of the Logan Square Neighborhood Association, was a constant presence in City Hall as he lobbied for progressive causes, from opposing drilling in the Marcellus Shale to bringing bicycle cabs to Philadelphia.

"He was like the 18th member of City Council," said Councilman Curtis Jones Jr., who eulogized Mr. Stuart Thursday.

Councilman Darrell L. Clarke also said he would miss Mr. Stuart, known to all as Rob. For this year's Strawberry Mansion festival, Mr. Stuart arranged for the Audubon Society to bring small animals, which thrilled the children.

"The kids just fell in love with it," Clarke said.

Mayor Nutter praised Mr. Stuart's contributions.

"Rob cared deeply about the city. He was a friend and a supporter, and I just feel terrible for his wife, Sarah, and the family," Nutter said.

Mr. Stuart was known as "the phone guy" because he carried what looked like an old-fashioned phone receiver, with a cord, in his shirt pocket. It was actually a device that he believed helped protect him from cellphone radiation.

One of Mr. Stuart's big skills was coming up with a new concept and getting others interested, said Sam Little, who succeeded Mr. Stuart as president of the Logan Square Neighborhood Association.

"He was like an idea merchant," Little said.

Phil Goldsmith, a former city managing director, worked with Mr. Stuart at CeasefirePA, which aims to reduce trafficking in illegal guns. He praised Mr. Stuart's foresight and passion.

"He was a tireless and optimistic social entrepreneur," Goldsmith said. "I didn't always understand his ideas, but I always knew it was something to make the city a better place to live."

Mr. Stuart was best known for persuading railroad company CSX Corp. to allow public crossings into Schuylkill River Park at Race and Locust Streets. Beginning in 2003, he waged a four-year battle to allow those crossings, using the Internet and other technology to marshal support.

"We knew that as soon as the park was built that hundreds of thousands of people would want to use it and that not having that public access was ludicrous," said his wife, Sarah Clark-Stuart, who worked with her husband on that and many other issues.