Wikipedia says:
Mount Paektu or Mount Baekdu (Korean pronunciation: [pɛ̝k̚t͈usʰa̠ɲ]), also known as Golmin Šanggiyan Alin in Manchurian and Changbai Mountain in Chinese, is an active volcano on the China–North Korea border. At 2,744 m (9,003 ft), it is the highest mountain of the Changbai and Baekdudaegan ranges. North and South Koreans consider the volcano and its caldera lake to be their countries’ spiritual home. Read more
The only way to get there for non-North Koreans is to approach from China side. The opening season for this park is from May to October, weather permitting. Each time we went there, we rented a van from Yanji in Yabian Province & drove 4 hours to get to the Changbaishan National Reserve area. You pay a separate fee for entering the park, for the shuttle bus within the park and the SUV tour to the peak. You have two choices to see the caldera lake on top of the mountain: take the SUV tour and spend 20 minutes on the peak and stare down or climb up 100’s of stairs to get to the lakeside. The weather is volatile in the mountain, and you may not be able to see much of the lake if the clouds hide it. We were extremely lucky to have the full view of the lake very first time we went there, and the picture above shows it. The second time we went up to the peak, we could not see much at all.
We tried the lakeside view twice. The first time was a near disaster because of the pouring rain. We went all the way out there, and we could not just turn back. The stairs were slippery, and there were lots of people braving the weather and crowding the stone staircase. The second time, we went in May, and there was nobody there and it was so quiet and beautiful. Too bad that not many photos have survived from these trips.
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We have not been there for many years, and I understand now there’s an international airport serving the area. There are ski resorts in the area, too. Here’s a link to a Chinese tour site.
Small Wide World 