1.5-mile walk around town in the dark, after the snow had fallen.
Marathoning on this day...  1996, I participated in the annual "Fat Ass 50" in North Adams, Massachusetts.  
This event consisted of many loops on the road, on a cold, gray day, and I believe there was a pretty bad snowstorm on the drive home.  
I have a time listed of  5:32:35, and I think that was for 26.2 miles - not 50k.  
This was my 8th marathon completed.