When I was 15 I started my linux days using gentoo, back in 2003/2004.
While the hassle of compiling and all the effort it took is laughable looking back on it, I still credit it for teaching me the command line and unix in general, these are skills I carry though with me to this day.
17 for me, and this is exactly how it is for me. Gentoo taught me Linux, and I have enjoyed it ever since. I use other distros as well, but Gentoo will always hold a special place in my heart.
While the hassle of compiling and all the effort it took is laughable looking back on it, I still credit it for teaching me the command line and unix in general, these are skills I carry though with me to this day.