Yeah, it's pretty close to a year round thing. For Champions League, usually the first qualifying round starts near the end of June, and the Final is played around the end of May. But, you have the games spread out where you're looking at two or three weeks between a game. Add it no games from mid December through early February and it stretches out.

As for the full details, well, I'll let steeler take care of that because I know I'll never do it the full justice like he can.

As for season schedules, the MLS is basically doing their own thing. Granted, the four seasons play into it, it's easier (and better for attendance) to run a MLS season from February/March through October. Most other leagues however, follow the international calendars and start in late July/August through mid May.