Day trip to Gero from Kyoto

Yes it's possible in a day trip but you need to start early as it takes about 3 hours to get there. You need to get on the JR Hida Limited Express 25. It takes you directly to Gero station. If your schedule doesn't fit, you can also get on the Shinkansen to Nagoya station and then change to the Hida Limited Express from there. You'll need to reserve your seat in either case.