I visited the subterranean river in 2007.

The underground river is one of the top attractions and was recently named one of the 7 Natural Wonders of the World.

While it is interesting, I would in no way put it among the top 7 natural attractions on Earth. I don't even think it is the most interesting cave, and it certainly isn't a greater attraction than the Grand Canyon, which beat out in the 7 Wonders contest.

If you are going to Palawan, I certainly recommend a trip to the underground river. Along with El Nido, it is the top attraction on the island, but I think its significance has been overstated with the recent 7 Wonders competition.

Read more about the Puerto-Princesa Subterranean River National Park on my website.