Lake Keyangen, known as the cleanest Lake in the Philippines, is one of the reasons why I came to Cologne. The guide pulled us to Kaiyangen at 9:30 because it was said that the morning view was the best. Registration is required before going up the mountain. The road to the viewing platform is not far, but slippery. It's better to wear sports shoes up the hill. The scenery of Kaiyangen Lake is not as gorgeous as it was previously seen on the Internet, but it's really very photographic.