Early 20's for me. No doubt. So much fun and independence, but we were old enough to not make the dumber mistakes we made in our late teens. College. Tons of travel on very little money. Live music every weekend. I was a total free spirit back then.
Disclaimer: This does not mean I don't love my life now......this does not mean I don't love my husband and kids.
***If you could go back and re-live any age from your past, what would it be? Now, you don't get to change things......just experience them again.