You found some tracks at the Site of Nilfgaardian Soldiers' Death. Follow them.
Follow the tracks from the Site of Nilfgaardian Soldiers' Death to the Broken Bridge (signpost), then get to the other side and continue following the trail southeast to a rocky area which you can climb to find the Griffin's Nest. See maps below.
"These prints are older, and deeper. Heavily armored. Nilfgaardians probably."
The Beast of White Orchard Quest
- Ask the Herbalist about buckthorn
- Find some buckthorn on the riverbed using your witcher senses
- Ask the hunter where he found the bodies
- Use your witcher senses to find the hunter
- Kill the wild dogs
- Talk to the hunter
- Follow the hunter
- Examine the site of the Nilfgaardian soldiers' death using your witcher senses
- Follow the Nilfgaardian soldiers' tracks using your witcher senses
- Search the griffin's nest using your witcher senses
- Talk to Vesemir
- Prepare to fight the griffin
- Meet Vesemir in the field where you plan to ambush the griffin
- Kill the griffin
- Take a trophy from the griffin's corpse
- Collect your reward from the Nilfgaardians