Boji is expected to travel up to 30 kilometers (18.6 miles) a day, passing through dozens of subway stations and taking at least two ferry crossings.

“He’s a very free spirit,” said Chris McGrath, a Getty Images photographer who recently spent a day following Boji around the city. “All he wants to do is ride public transportation. Every time he passes a bus or a van or any kind of transportation, he just wants to get on it. It’s really quite strange.”

McGrath first saw Boji on Twitter, where people post photos and selfies of themselves with the mixed breed dog. Now the dog even has his own Twitter and Instagram accounts with tens of thousands of followers.

“Everyone knows him now and everyone has seen him,” McGrath said.

For many, the dog has become a beloved member of the community.

“He walked into a restaurant and two men chased him away and yelled at him,” McGrath said. “And then you hear someone else, the owner of another restaurant, yelling at those men: ‘It’s Boji! It’s Boji! Don’t chase him away!’ So he clearly has celebrity status now.”

The city staff is very protective of Boji and have been taking care of him. Earlier this month, they took him in to get him groomed and have a medical exam. They also conducted a behavioral study to make sure he was okay and that all human interaction wasn’t a problem for him or the people around him.

“They took him to a training camp and gave him some TLC, some grooming and some shots,” McGrath added. “They watched him interact, fixed his tracking collar and that took about a week.”

The municipality even installed a small cage for him in one of its Metro stations and feeds him every time he wants to return.

City staff monitor Boji from afar, using a smartphone app to track his activities. McGrath teamed up with them last week for his day after Boji.

“He knows exactly where the doors are on the trains,” McGrath said. “He stands on the side of the platform, and as soon as he feels the vibration of the train approaching, he walks to the end of the platform and then basically chases the train and waits at the door. He knows exactly where the doors are. He’s actually pretty forceful; people are trying to get ahead, he’s trying to get on.”

When Boji boards a ferry, he knows exactly where to go: to the side of the sun.

“He likes the water,” McGrath added. “When the ferry starts to sail, he starts barking at the waves.”

“He checked one and people were getting on. I don’t know how he knows, but that one was headed to Eminonü. And the second one was headed to Beşiktaş. Then he checked the one to Eminonü and decided no, that’s not the right one. And then he went under the turnstiles and went to the one to Beşiktaş. I don’t know how he knows, but he seems to love riding the Beşiktaş ferry.”

“On the ferry, he sits in the back where the engine is, because he likes the vibration,” McGrath added. “And then when he’s on the Metro, on the subway, he sits where the wheels are, like underneath, on top of the wheels. He always likes that feeling of sitting on them.”

It is this region of the metro that Boji gets its name from. In railway parlance it is known as the bogie region, and bogie translates to boji in Turkish.

If there’s one thing Boji doesn’t like, it’s cats. And on his travels he comes across several stray cats.

“Istanbul is called Catstanbul because there are so many cats here,” said McGrath, who has lived in the city for six years. “(Boji) sees a cat in the distance and just chases it. I saw him do it three or four times, chasing them up trees and all that. He doesn’t really like cats.”

“But other than that, he’s a really great dog. He just walks around. Everyone pats him. He’s extremely happy.”

Because there are so many stray animals in Istanbul, it is not difficult for Boji to get food.

“There will be water and a bowl of food for the animals discreetly hidden in the corners of restaurants or houses,” McGrath added. “So (Boji) knows where to go.”

“He was on his way to the ferry, and there was a taxi stand and there was a little cat shelter and some bowls and he stopped there and drank. And there’s a picture of him on the subway drinking, and that’s like a municipality’s animal food and drink place. I knew exactly that I had to go there.”

McGrath said the city will soon be putting up some informational signs about Boji on the public transportation system, offering people some tips on how to interact with him.

But don’t expect the dog to obey commands.

“He doesn’t listen to anybody,” McGrath added. “Like if you tried to tell him something, he would just ignore you. A lot of people say, ‘Oh, come here, sit here,’ and he just ignores them and goes wherever he wants to go.

“He’s definitely that kind of spirit. He just wants to do his own thing and travel, and he’s pretty happy with that.”