I am a little bit unsure which frame size I need. I am looking at the CAAD4 mtn frames.
Can anyone help me? I am 180 cm tall

Thanks
HL

Medium. But don't take my or anyone elses suggestion...go and test ride different sizes and buy the one that feels the best.

When you test ride one, make sure it has a 100mm stem with the seat in the middle position. This way you can fine tune it later on for a 140mm or 50mm stem and be able to adjust the seat.

IMO: The Cannondale hardtails are designed/sized to give you a slightly more stretched out ride... Personally, I look for a smaller frame hardtail (if not xc racing).

Medium.

Thanks. I went to a dealer today, and I noticed that the M - size was perfect, at least when standing over the bike. Unfortunatley, I could not go for a test ride, but it felt like I had a good position when sitting on the bike.