Kim Jong-un has crossed the border into the demilitarised zone between North and South Korea - the first North Korean president to do so since 1953.
There, he shook hands with South Korean president Moon Jae-in, ahead of a summit focused on denuclearising the Korean peninsula and improving inter-Korean relations.
"New history starts now," Jong-un wrote in the visitor's book at the Peace House, where the summit is being held, according to Reuters.
"Age of peace, from the starting point of history."
The demilitarised zone is a strip of land separating the two countries and has previously been the meeting point where negotiations take place. It is widely being reported Jong-un has entered South Korea, however the land does not lie in the territory of either country.
The neighbours are technically still at war after the 1950-53 conflict ended with a ceasefire, not a truce.
In March, Jong-un pledged to commit to denuclearisation as tensions ease between the old foes.
Tension over North Korea's tests of nuclear weapons and ballistic missile surged last year and raised fears of US military action, after North Korean threatened to develop a nuclear weapon capable of hitting the United States.
But this tension eased significantly after the North decided to send athletes to the Winter Olympics in South Korea in February.
On Friday the White House released a statement wishing the people of North and South Korea well.
"We are hopeful that talks will achieve progress to were a future of peace and prosperity for the entire Korean Peninsula," it reads.
"The US appreciates the close coordination with our ally, the Republic of Korea and looks forward to continuing robust discussions in preparation for the planned meeting between President Donald J. Trump and Kim Jong Un in the coming weeks."