I proudly report I once spent 1,5hrs on my 15km commute. Average speed 10km/h, top speed 14km/h. I consider that a personal record of sorts, because I had to work hard for every bit of it. It was snowing heavily and had been for a while. MUPs hadn't been cleared yet, there were snow banks up to hub level, with occasional hard packed stuff thrown into the mix by plows clearing the adjacent street.

I was spinning like a squirrel on crack for 90 minutes. Hardest workout I've ever had during my commute.