The latest protest drew hundreds of thousands of demonstrators, with 1,000 people flying in from the southern resort island of Jeju.
Thousands of men, women and children converged on the streets of Seoul, South Korea on Saturday to participate in one of the biggest anti-government protests seen in the country in decades, demanding the ouster of President Park Geun-Hye over an escalating corruption scandal.
Park is facing the worst political crisis of her four-year presidency as South Korean prosecutors investigate her friend Choi Soon-sil on charges of meddling in state affairs and forcing companies to donate funds to non-profit foundations.
Police said that around 260,000 people turned up at the protest, while organisers put the number at about 1 million.
It is the third in a series of weekly mass protests against Park, whose presidency has been shaken by the scandal.
Police deployed around 25,000 officers to keep the calm, many of them in complete riot gear, while police buses and trucks blocked every major and minor access road around the presidential Blue House.
The crowds consisted of an extreme mix of people, with high school students standing alongside retirees, labourers, farmers, Catholic nuns and young couples marching with babies or young children.
"Park Geun-Hye must resign because she didn't take good care of our country," said 11-year-old student Park Ye-Na.
Protester Cho Joo-Pyo and his family had travelled from Jeonju, about 200 kilometres south of Seoul, to join in the protest. They were just one of tens of thousands who took trains or buses from towns and cities across the country to demonstrate.
A group of 1,000 protesters flew in from the popular southern resort island of Jeju.
The atmosphere was mostly peaceful, with people chanting slogans and the noise of the steady beat of drums in the background. There were banners everywhere ridiculing Park and calling for her immediate resignation.
As night fell, Seoul's main ceremonial boulevard Gwanghwamun lit up with flickering candles held up by demonstrators.
In a televised news conference on Friday, Deputy Prime Minister Lee Joon-Sik expressed concerns at the possibility of "illegal collective action or violence" and called on protesters to adhere to police barriers.
Saturday's rally also put the focus on several other complaints, from plunging rice prices to the government's handling of the 2014 Sewol ferry disaster.
Withering the storm
Park has issued several apologies, reshuffled top officials and even agreed to give up some of her extensive executive powers, but this has not been enough to stop the constant calls urging her to step down.
Park has just over one year left until the end of her single five-year term. Most experts believe she will be able to overcome the crisis and remain in office, despite her authority and ability to govern being greatly undermined.
Opposition lawmakers have appeared more interested in pushing for further concessions from Park, rather than taking calls for her resignation into consideration.
The candlelight rally began at 4:00 pm (0700 GMT) at Seoul City hall, with a plan to march along four different routes towards the Blue House.
A last minute court order removed some of the police road blocks, but the protesters were to be kept more than a kilometre away from Park's official residence.