Amid tension over North Korea's nuclear test, tourists visited an observatory in South Korea on Friday (October 13), where they could gaze through giant binoculars to sneak a peak at their reclusive northern neighbour. The Unification Observatory is located just south of the 248-km (154 mile) demilitarised zone (DMZ) which divides the two Koreas. One million troops are believed to be massed on either side of the DMZ with enough artillery to turn large parts of the rival Korean states to ash. Seoul is a mere 50 km (31 miles) from the border. For Lee Kang-moon, 50, standing so close to the North made tension over its nuclear test more tangible and threatening. "I wish our country reunified because we keep fighting even though we are the same race. I wonder if a war would break out, and I worry," said Lee. The two Koreas technically remain at war, as a peace treaty was never signed after the 1950-53 conflict. Yet Yoon Doo-hyun, 80, who was a young man during the Korean War, doubts another war would break out. "I don't think they will fire at us just because they said they made nuclear weapons. They won't and I don't think they can," he said. Sayuri, a tourist from neighbouring Japan, hoped that North Korea did not conduct a nuclear test. "I hope they do not test nuclear weapons because the nuclear material will be blown all the way to Japan and that will be harmful for people in northeast Asia," she said. President Roh Moo-hyun has said South Korea's military is prepared for any North Korean provocation. North Korea conducted an underground nuclear test on Monday (October 9), flying in the face of a warning from the U.N. Security Council and opening its crippled economy to the risk of fresh sanctions.