What is the most impressive feat of strength you have ever done?

I once yanked a really large root out of the ground. I was pulling on it so hard I thought I was going to blow out various muscles, but then it came up--it was several feet long. 

My strength seems to often show itself in feats of epic gardening. :D

The last time I had a membership at a Jack LaLanne health club, I could bench press 125 lbs.  That was about 40 years ago.  Now, the heaviest thing I lift is myself out of bed in the morning.

I was nine years old when I gave my father a piggyback around the garden.

At art school, I once helped unload the sandstone blocks from a lorry while attempting to keep equal pace with the guys.
My back was seriously sore for three weeks.
Ever since then I've used mechanical aids to lift anything heavier than 20 kgs.