Day Trips from Assisi?

The two are only about 20 miles apart, so perhaps you needn't be limited to places right on the way? Elsewhere in the immediate area you have Perugia (larger) and Spello. Todi is a good way beyond Deruta but looks like it would still be manageable on the same day.

You might want to take a look at ViaMichelin, because there are some green-shaded (scenic) roads marked in that area.

After visiting Spello from Assisi by car, I continued on to Bevagna and Montefalco. All 3 towns were interesting, and you could design a loop to include those 3 towns plus Deruta. I took another day trip north to Gubbio and Urbino, both of which I enjoyed a lot.

In Deruta, you will be overwhelmed by many levels of quality in ceramics. The oldest ceramiche , from 1500, is Ubaldo Grazia. We bought several beautiful pieces there and had them shipped to our home. I use them all, almost daily. Even if you don’t buy anything, it is a beautiful place to visit. Skip the many ceramiche lining the road into town.
Spello, Montefalco, Bevagna can be seen together and Perugia would be an interesting day trip, not necessarily en route to Deruta. . The parking garage below Perugia has escalators up go up to the historic city center. No escalators down , however.
Spello is ringed with parking lots that are sometimes hard to find. There is one at the top that we used when we rented a house there. Bevagna is flat, a nice sjrprise.

Thanks everyone for the great recommendations.

Just wanted to add my thanks as I am planning a similar trip in October but from Cortona for 4 nights. Had not picked the towns and had no idea where to start with this one. Beautiful places.