genre of music

by Steve
(Leicester)

Hi, on a recent holiday I came across a type of music that I have not heard before but really liked, I have no idea what it is, it has a very heavy repetitive monotonous baseline, and that's just about all, it repeats over and over with slight key changes here and there and goes on for ages. It is not just one tune I'm looking for but the genre, can you help? Steve.