Answer first: Urbino is a UNESCO city with Renaissance buildings; Frasassi is the cave. Do Urbino in the morning and the caves in the afternoon, but check the drive time on your map.
Urbino
UNESCO listed the historic centre in 1998. The Palazzo Ducale, built for Federico da Montefeltro in the 15th century, houses the Galleria Nazionale delle Marche. Raphael’s house is here too (Wikipedia). Palace hours and prices were not verified.
GetYourGuide lists tours with the Ducal Palace, rated up to 4.9.
The caves
Pick a later cave slot, and buy tickets in advance.
Stay
Frequently asked questions
Is Urbino worth combining with Frasassi?
It suits a full day with an early start. Distances are about 60 km but the drive time is unverified.
What is in the Palazzo Ducale?
It houses the Galleria Nazionale delle Marche (Wikipedia). Raphael's house is also in Urbino.
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