I just came back from Lashio, the town of Northern Shan State. On my way back, I went and visited to Peik Chin Myuang cave( (also known as Maha Nandamu Cave) which is is located on the Lashio road near Wetwun village, 12 miles east of Pyin Oo Lwin town.
Actually, It is a limestone cave estimated between 230 million and 310 million years old. (just they said, I'm not sure) .
The cave is called Peik Chin Myaung as plenty of Peik Chin plants used to grow there.
The entrance of the Peik Chin Myaung cave is about 20 ft wide and 1,600 ft long. So, it's a big and long cave.
The long cave is filled with so many Buddha images and pagodas in various sizes and position at every corners and niches.
It's really worth to visit! Don't forget to go there when you reach POL or Lashio.