The election is the first since the historic peace deal in 2016 with rebel group Revolutionary Armed Forces of Colombia (Farc) that contributed to decades of civil war in the country.
Monsignor Hector Fabio, director of Caritas Colombia, and president of Colombia's National Peace Council told Premier that while the deal has brought some stability to the country, there's still a long way to go.
"After the peace agreement, so many steps have been taken, but we have a long way to go. Negotiations with the National Liberation Army (ELN) move slowly.
"New armed groups try to control the rural areas. And, last year, 121 human rights defenders were murdered – the deadliest year on record," he said.
Voters have the choice of Iván Duque and Gustavo Petro.
Mr Duque is the handpicked candidate of Alvaro Uribe, the ex-president and chief critic of the nation's 2016 peace deal with the Farc. He is promising to amend important aspects of the accord, such as ensuring drug trafficking is not an amnestied crime and blocking guerrilla leaders from political office.
Mr Petro supports the accord and has galvanised youth voters angered by corruption and income inequality. He is vowing to end Colombia's dependence on oil exports and raise taxes on vast swathes of unproductive land in the hope of boosting agricultural production.
Monsignor Fabio said that he's praying that the outcome of the election brings peace, unity and healing for the 8 million Colombians who have suffered from internal conflict.
"It is not easy to overcome a situation like we've had in Colombia; five decades of internal conflict, destroyed communities, while others are bitterly divided.
"What I hope is that the new government in Colombia will continue implementation [of the peace deal] and will make changes for the peace in Colombia.
"This is an opportunity for the new government to help society move forward, to show their commitment to the security of the country and their willingness to invest in the implementation of the peace agreement."
Listen to Monsignor Hector Fabio speaking with Premier's Tola Mbakwe here:
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