This is probably a stupid question, but I was wondering about this on my flights this last week. Do the airlines fly generally fixed routes from city to city? For example, if SWA was flying from MCI to SEA, do they generally fly the same path (making allowances for weather etc)? Also, are those routes published anywhere? I've looked on airnav.com and airlines.net. I'm asking because we came into Seattle at night from the south and I'm trying to figure out one of the cities over which we flew. Thanks!