Horror book about a hotel and caves, I thought it was by James Herbert but I appear to be mistaken. Help!?

A few years ago i read a horror book i assumed was by James Herbert but it appears i was wrong. Its similar to the movie The Descent but this is about a hotel that is above caves that are a tourist attraction. It appears there are murders in the hotel and a group of inbred creatures live in the caves. A tourist group gets stuck down in the caves and they have to fight to get out. The author also wrote a book about a serial killer who was invisible and a butcher?!? I don't know what happened there as i stopped reading it as it was pretty sick and twisted. I was explaining about the book to my friends but they have never heard of it. Google doesn't appear to know it either.