There's a lot to love about BARTy.

BARTy is BART's mascot, and if you live in the Bay Area, there's a good chance you've seen the cartoon train out on the town (or on social media). It's got big dewy eyes, perpetually blushing cheeks, and a square head-slash-body. You can't miss the lil' guy and its smattering of accessories, be it binoculars, rainbow sweatbands, or a Ballers baseball cap.

Since 2019, BARTy has been appearing on BART t-shirts, stickers, graphics, and signage. There are now more than 20 iterations of the anthropomorphized train - sugar skull BARTy, cricket player BARTy, Frankenstein's monster BARTy, etcetera.

But before all that, BARTy was a seven-year-old's sketch.

It was winter break in 2019, and BART graphic designer Joe Lash brought his seven-year-old son to the office with him. There was much to be done in the office that day, and Lash needed something to entertain his kid while he got some work done.

"That year, I was tasked with designing a t-shirt for employees to wear in the Chinese New Year Parade in San Francisco," Lash remembered. "I was coming up with a bunch of concepts, and I said to my son, 'Why don't you draw some, too?'"

His son got to work sketching. Every one of his designs featured a square train with a smiling face, and because it was the Year of the Rat, the seven-year-old added a rat and cat "dabbing" on top of the train.

"That drawing didn't make the final cut, but the square train design did," Lash said. "That was the birth of BARTy."