Hard. I scheduled a 51 mile ride for our club, but only one other person signed up. He's a slower rider than I usually am, so I took my heavy steel gravel bike instead of one of my usual aluminum or carbon fiber race bikes.
We had a nice conversational pace ride averaging 15.8 mph over that distance. (Last time we did that route, I was on the road bike, and I averaged 18.7 mph. But we had more people, and some of them are pretty strong.)
But man it felt so hard. Just felt like I was struggling all day. I had a snack about 15 miles in and kind of mentally reset - refocus on spinning the pedals, not grinding it out. From there I felt better, but it never felt like an easy ride.
Last weekend we did a four day, 315 mile tour (at an easy pace, not a race), so I might just be struggling from that yet, too. I felt good when I rode Tuesday night, but Thursday morning on zwift felt pretty difficult, even though I wasn't pushing hard. I probably should have taken a rest day today.
Tomorrow, my wife and I and a few others are running a rest stop for a local charity ride. A nearby restaurant supplies bread pudding as a treat for the riders (and us). It's so good! Of course we also have other snacks, water, gatoraid, pickles, etc. Coincidentally, one of the owners for the bike shop I work at will be providing mechanical support at the same rest stop.
The Biketoberfest looks fun.