Beautiful sunny evening last night, and my wife and kids are away, so I drove up to Ashbourne after work to run on the Tissington Trail, with a vague notion of doing 15-20 miles.  I've not run more than a HM since 
last summer, and only ran 13.1mi once in preparation for the Uttoxeter Half, so this would be a Big Run.  I had a banana and a gulp of water before I started, and set off with another nana and a small screwtop bottle of water in my hands - not really as much as I'd have wanted.
Started quite steady.  The trail is mostly very gentle uphill north of Ashbourne.  I was just inside 8:00/mi and ticking along comfortably.  7, 8, 9, 10 miles came and went.  By the time I got to Hartington, I was pretty much committed to running a marathon.   I turned at 13.15 miles (for the Strava tax), just under 1:44, and was still feeling pretty good - even, better - as the track headed back downhill.  My only proper marathon was 3:23 (also on the Tissington Trail, but turning at Parsley Hay and finishing in Cromford), and, although I wasn't going to beat that, I realised I could still beat 3:30.   I was clocking 7:45-7:50 miles pretty much to the end.  It got a bit grippy around 24 miles, as I tackled the stop/start of winding through gates, and I was starting to feel a recurrence of the blister I'd suffered at the Uttoxeter Half.
There's a short stretch of 1-in-8 on Mapleton Road, just leading back into town.  Nearly killed me.  Ticked over 26.2 within sight of my car, just inside 3:27.
Legs had seized up a bit by the time I got home, so I had to psych myself up a bit to get out of the car.  Quick raid of the fridge and a couple of paracetamol.  Getting upstairs, and in and out of the shower, was a bit of a trial.  Then sleep!
https://www.strava.com/activities/14624419184
EDIT: I went for a DOMS rehabilitation spin last night for just over an hour.  Near the end, I got tempted to smash one of the little hills.  Despite the sore legs, I managed 644W for the 1:04 Strava segment (a PB of 667W for a minute).