Last night I was thinking about the trill sounds and how most languages I know about have just one, though they vary in which one they have.
Most common seems to be the alveolar trill
/r/, as in Italian, Spanish, and many languages.
Then German, depending on the variety, has the uvular trill
/ʀ/ which I can seldom produce.
The only language I am familiar with that has two contrasting trills is Czech, with an alveolar trill, and its famous/unique fricative trill,
Caveats: Yes there are languages such as German that have two non-contrasting trills, which those sounds being allophones distributed among the varieties, and languages which contrast a trilled "r" with one or more other types of "r" such as taps/flaps. I'm not concerned with those for this question.
But are there some less well-known languages that have three or more contrasting trills?