Completed the first running of the "Tour de Greylock" on August 8th, 2020. This is a route I've been planning for several months - the intention was to do a complete loop around Mt. Greylock, hitting as many of the most notable landmarks as was feasible. Highlights include ascending the Thunderbolt Ski Trail, the plane wreckage off of Bernard Farm Trail, the beautiful Money Brook Falls, and the Stony Ledge amd Propect Mountain overlooks. Two full summits of the mountain (one from the east, the other from the west), and a third significant climb up Mt. Williams.
The run was (minimally) self-supported; I left caches of water at the Bellows Pipe amd Haley Mountain trailheads, as well as at the Jones Nose parking lot (approximately miles 8, 15, and 24). Had a water filter with me but did not need it. Carried all of my nutrition.
Weather conditions were good - mid/upper-70° through the day. Clear during the day but it had rained the night before, which slowed down many of the more-rocky descents (especially in the first half of the run). I do not believe this significantly impacted my time - maybe on balance, 10 or 15 minutes.
No significant issues along the way - was able to make steady progress throughout. Lots of hikers in the middle section (near the summit and near Mt. Williams) but mostly very quiet.