Spurned apologies
In an effort to soothe public anger, Park has issued several public apologies, voicing her personal "heartbreak" at being the cause of such widespread anger and distress.
She has also reshuffled top officials and even agreed to relinquish some of her extensive executive powers, but the popular calls for her to step down have been relentless.
"She has apologised but I don't think it was sincere," said college student Ahn Ye-jin.
"As Korean citizens, it is up to us to bring about change in this country and that is why I am here today. Park has to go," Ahn said.
Most experts have suggested the president, who has just over a year left of her single five-year term, will be able to ride out the crisis and remain in office, albeit with her authority and ability to govern seriously undermined.
Opposition lawmakers have largely avoided direct resignation calls and appear more interested in extracting further concessions from Park in terms of devolving power to the legislature.
But the sheer size and volume of Saturday's demonstration will be impossible to just ignore.
"Judging from what I saw today, people's resentment against her is simply too strong for Park to stare this down," said Lee Yeon-Ho, a political science professor at Yonsei University.
"People are literally seething with anger," Lee said.