North Korea has agreed to "permanently" abolish its key missile facilities in the presence of foreign experts, says South Korean President Moon Jae-in.
Mr Moon and the North's Kim Jong-un have hailed a new future for the two Koreas, signing a wide-ranging agreement in Pyongyang.
The two sides have "agreed on a way to achieve denuclearisation," Mr Moon said.
North and South Korea also plan to link up railways, allow family reunions and co-operate on health care.
The summit results were described by Mr Kim as a "leap forward" towards military peace.
"The North agreed to permanently close the Tongchang-ri missile engine test site and missile launch facility in the presence of experts from relevant nations," Mr Moon said after the signing.
Mr Kim said he had promised his Southern counterpart he would "visit Seoul in the near future" which would be the first visit of a leader from the North to the South's capital.
The two countries will also seek to co-host the 2032 Summer Olympics.
The South's defence minister and the head of the North Korean military also signed an agreement.
North Korea has embarked on an unprecedented series of meetings this year with both the South and the US.
The signing comes during a three day visit to Pyongyang by Mr Moon.
While it is the first trip to the North Korean capital in a decade by a leader from the South, it is Mr Moon's third meeting with Kim Jong-un since their historic summit in April.
But efforts towards denuclearisation between the North and the US had recently hit a deadlock and there's hope the South will act as a mediator.