And as the first bus pulled up to the entrance, 23-year old Shihan Wijeyeratne stepped down onto the ground and became the first runner to arrive for the 121st running of one of the world's oldest and most famous footraces.
Eight years ago, she started running marathons again after a break of nearly 30 years.
"I'm so excited about Monday".
At the time, women were woefully marginalized in the world of athletics.
Tales of Arnie running the race motivated Kathrine to make that her goal. Geoffrey crossed the line and claimed the Men's 2017 Boston Marathon championship! "I was afraid, because you know, if you miss water it can affect you".
For Kirui, even when he was running shorter distances, he had his eye on Boston. I grinned through the gloom and flakes. When she was just a 20-year-old Syracuse University journalism student, Katherine attempted to break barriers by registering in the race.
The pair practiced together and when Switzer sailed past the finish line of a 26-mile run easily and made a decision to tack on an extra five miles for good measure, she proved to her coach she was ready.
Switzer was ready to run the Boston Marathon, coach Briggs was ready to support her - but the world wasn't. I was serious about my running and I could not let fear stop me'. "A big man, a huge man, with bared teeth was set to pounce, and before I could react he grabbed my shoulder and flung me back, screaming, 'Get the hell out of my race and give me those numbers!'"
The run in made Kathrine think for a split second about quitting the race, but she chose to press on.
On Monday, Switzer will run wearing the same number once stripped from her by an angry man who didn't want to see a woman in his race.
In 1967, Kathrine Switzer was the first woman to run #BostonMarathon as a registered entrant.
An advocate for equal rights in sports, Switzer successfully campaigned for the Olympics to adopt the women's marathon as a sport in 1984. She started the nonprofit 261 Fearless in 2015, which uses running to empower women around the world.