We were slower on the return trip, which I've decided to explain away in a faith-based analysis that the trip back was uphill. We stopped in McKeesport at the convenience store for cold water and Gatorade. Continued via Glassport and Clairton back to Large, where we stopped again in a shady spot.
Today definitely felt like a harder day to ride. We stopped at another conveniece store, and they had the reefer door open and I greedily stood in front of it trying to cool off.
At the National Tunnel I stopped for another cooldown among the cold stones, and that was very nice. A few more miles to our uphill destination, but there was no question of walking up the hill in R's neighborhood and it felt like a nice way to finish.
It was 87F when we got off the bikes at 1330. I'd drank at least three gallons of water over five and a half hours, and was still impressed at the effect of the heat.
This was an excellent Pittsburgh S24O (sub 24-hour overnight), easily accessible from the city via the new Sandcastle trail, and also accessible with a little bit of navigating and road sharing via the southern arc of the Montour Trail. Highly recommended.