Hotel Grad Otocec

This Relais & Châteaux hideaway, set on a slim island in the wide, countryside-wrapped Krka River, has the crumbling conical towers and stone-clad wine cellar you’re after. But there’s also a fine-dining restaurant worth making a detour for, too; tuck into roasted quail breast, grilled lake fish and desserts made from local pumpkins before retreating to plush, polished rooms in caramel hues.