Any recommendations for a 2-3 hour hike round trip starting from Assisi? We are a reasonably fit couple in our 60's. Thank you in advance for your ideas.
You could go up to the Franciscan Sanctuary Eremo delle Carceri (4 km, uphill, rather steep).
In theory you could consider also the cycle path (where you can walk too, of course) Assisi-Spoleto, obviously not as far as to Spoleto but to the nice village of Bevagna; the path is flat but Bevagna is some 15 km from Assisi, so you'd need to allot much more than 2-3 hours round trip!
You could always take a taxi up to Eremo delle Carceri and then walk back to town ... we did that in 2007 while on a Franciscan Pilgrimage. Fantastic walk and great views on your way back to town. Well worth the hike.