How to deal with period on holiday tips?

Soo, I'm on vacation with my family and a few friends and I just got my period yesterday. We plan to do long walks up mountains and perhaps even swimming which sounds like a nightmare, I really don't like tampons lol. No one in my family or any of my friends is really open to this stuff; I prefer to keep it to myself, so that's why I'm here! I just wanna keep my period private and still have a good time without dying of cramps and embarrassment. Help!!