Now she's been reunited with the rescuers who saved her life.
In the rat race of New York City's morning commute, the feisty little dog stole the show Tuesday morning.
"Most importantly, we wanted to have that dog alive. I'm a dog lover," said MTA police officer Luis Alvarez.
The three-year old collie sheperd mix decided to race a Hudson Line train headed to Grand Central, literally running on the parallel track and even in front of the moving train for more than a mile, from 149th Street to 125th Street in Harlem.
The pooch even crossed a bridge.
"You have live rails there. You can definitely get electrocuted," said Alvarez.
The train engineer slowed to a crawl to protect the dog, and many customers soon peered out of their windows to cheer on the sprinting pup.
Eventually two MTA officers, both dog lovers themselves, were able to round up the dog at the Harlem station.
In fact, the friendly pup came right toward the cops.
"We whistled, we called, and it came actually came to us, so it was actually very happy to see somebody," Alvarez said.
Animal Care and Control is now taking care of the fun-loving dog, who has no identification but has earned an affectionate new nickname.
"Her name is Tie because of where she was found, along the railroad ties," said Risa Weinstock of Animal Care and Control.
Tie is clearly a fearless pooch, unfazed by trains or by cameras.
"As you can see, she's raring to go. Healthy, happy and looking for a great home," said Weinstock.
Officials are hoping that all this media attention will prompt the dog's owners to come forward. If not, Tie will be put up for adoption on Friday.