I love this thread!
I never take running for granted. I think this happens even more the older I get. I remember the first time I ran 2 miles as a 13 yo. I was so happy! Then, it was 4 miles. And then 8. I remember how hard 8 miles used to be for me in HS.
As for running for a "long time" ha, my limit is three hours. My husband is able to read the Sunday times in the time it takes me to run 20 miles.