The Swiss foreign minister has become the first foreign government official to cross the demarcation line separating North and South Korea.
After completing the symbolic act, Micheline Calmy-Rey said Switzerland was prepared to act as a mediator to resolve the nuclear stand-off in the region.
Calmy-Rey crossed the heavily fortified border to the village of Panmunjom early on Tuesday, after travelling through the four-kilometre buffer zone.
"It was a small step, but I hope it will be a big step for peace in the region," she told swissinfo's Juliet Linley in Panmunjom.
Describing the event as a symbolic act, Calmy-Rey said it demonstrated the possibility to overcome lines and borders - symbols of separation and confrontation.
"As a small country Switzerland builds its security on the respect of international law and peaceful settlement of conflicts," said the Swiss foreign minister.
"This event shows for me that limits and borders can be overcome if we build on confidence and trust, and avoid confrontation."
Her journey across the historic divide came at the end of a four-day visit to the North. She is due to spend two days in South Korea before heading off to China on Thursday.
During her visit, the Swiss foreign minister held talks in Pyongyang with her North Korean counterpart, Paek Nam Sun, as well as with other senior government officials.
The issue of North Korea's nuclear programme came up during discussions, and Calmy-Rey said the Swiss were prepared to play the role of facilitator to help resolve the seven-month-old crisis.
During talks between Washington and Pyongyang in Beijing last month,
US officials said the North claimed it already had nuclear weapons and was prepared to use or export them.
"Concerning security we agreed that it can only be reached through a continuous process of dialogue among all parties concerned," said Calmy-Rey.
"It is essential to increase confidence between the parties, within a transparent environment and a spirit of compromise and peace."
However, just as Calmy-Rey made her appeal for a resolution of the nuclear crisis, Pyongyang warned its neighbour against criticising its nuclear programme.
"The South side will sustain an unspeakable disaster if it turns to confrontation, talking about the 'nuclear issue' [with the United States]," said Pak Chang Ryon, chief North Korean delegate to inter-Korean economic talks held in Pyongyang on Tuesday.
Seoul and Washington last Wednesday said they "will not tolerate" nuclear weapons in North Korea and agreed to consider "further steps" if Pyongyang escalates tensions.
During her trip to the North, Calmy-Rey also stressed the importance of human rights and said she was encouraged that North Korean officals had accepted that dialogue on the matter was necessary.
The Swiss foreign minister also visited a number of Swiss-sponsored development aid projects in the country, in addition to holding talks on future humanitarian cooperation.
It is extremely rare for anyone to be allowed to cross the Cold War's last divide. Normally travellers fly from Pyongyang to Beijing before taking a plane to Seoul.
In 1994, during a similar nuclear crisis, the former United States president Jimmy Carter also got the green light from North Korea.
According to Swiss officials, the offer to cross the demarcation line was the fruit of "satisfactory" cooperation between Bern and Pyongyang.
"The positive response to this invitation is proof of Switzerland's desire to be useful as far as possible," said Christian Mühlethaler, Swiss ambassador to Seoul.
Political analyst Hans Hirter said Calmy-Rey was hoping to use the visit to the two Koreas to raise Switzerland's diplomatic profile around the world.
"She wants to play an active role and show not only Swiss citizens, but everyone in the world, that Switzerland can be a dynamic partner in looking for peace and freedom," he said.
However, he doubted whether the high-level visit would have any impact on relations between the neighbouring countries.
He added that the crossing was more of a symbolic gesture tied to Switzerland's traditional role as a monitor of the 1953 ceasefire, which ended military hostilities between the two neighbours.
"It's probably just the United States, China and the two Koreas themselves that have the power to change anything there," Hirter said.
Nevertheless, the crossing highlighted Switzerland's concern about the escalation of the nuclear crisis, Philippe Régnier, director of the Modern Asia Research Centre at Geneva University, told swissinfo.
"This gesture went some way to easing a very tense situation," Régnier commented.
Switzerland has been one of two countries - the other is Sweden - to have personnel permanently stationed at Panmunjom since 1953, as part of the Neutral Nations Supervisory Commission in Korea.
swissinfo, Juliet Linley in Panmunjom