Philadelphia's gritty, colorful, and ever-popular Instagram attraction, Graffiti Pier, was shut down Tuesday.

Police in the 26th District sent out an alert saying officers would enforce a no-trespassing ordinance at the former coal-loading pier that juts into the Delaware River at Port Richmond. Cars parked near the entrance on Beach and Cumberland Streets will be ticketed and towed, authorities announced.

The area has been private property — and technically closed — since its owner, Conrail, installed a locked gate in 1991. But that barrier is easily traversed, and tourists and locals alike have visited undisturbed for years.

Police said an increase in illicit activity, sparked by a surge in tourists to the area, has changed all that.

Conrail did not immediately respond to a request for comment.

"People are coming from outside the city who read about it and want to get pictures of the pier," said Capt. Krista Dahl-Campbell of the 26th District. "They come down, they leave their cars unlocked, come back, and their stuff is missing."

Dahl-Campbell said there's also the risk of more serious crimes. In recent years, she said, police have responded to robberies, assaults, a rape, and a drowning on the property.

"I think people think it's like a city park or attraction, but it's not … ," she said. "It's private property, and it's not cared for. It's not safe. There's nobody watching out for you back there."

Back when it was in use, Pier 124 was a loading dock for ships transporting coal. Over time, the abandoned, vast concrete walls and passageways have become canvases for graffiti artists and a playground for paintball enthusiasts. Lovers of the space have advocated for making it a protected public park to prevent its closure.

Kae Anderson, director of economic development for the New Kensington Community Development Corporation, said some community groups periodically clean up the area, which often attracts illegal dumping.

While iconic, Anderson said, it's unsafe in its current condition.

"I would love to see that space become something that could be activated and could bring that connection back with the river," Anderson said. "But in the state it's in now, it's not conducive nor is it safe for public gathering."

Conrad Benner, founder of the street art blog, said that if the city was worried about violent crime, arrangements should be made for officers to patrol the area.

"I guess we'll have to wait to see what exactly this new enforcement looks like," Benner said. "But, if it means eliminating what has effectively operated as a public space for the neighborhood for many, many years, then I think that is an enormous loss not only to the graffiti writers, street artists, photographers, and neighbors that use the space but also for the city.

"This is a special spot. The kind of city-defining spot that most cities would kill to have. Seriously, the graffiti writers that have shown this abandoned pier love for over a decade now have helped to make this one of the most stunning, ever-changing spots in the city."