Castell del Rei, the King’s Castle, is one of the three remaining rock castles on Mallorca. Few people know about this imposing structure near Pollença. For one thing, it is perfectly camouflaged. Another reason is that it is privately owned and a protected area for the rare monk vulture. And so the path that leads through the Vall de Ternelles is still an insider tip. Guided Tours Equipped with binoculars and a bit of luck you may spot the emblematic bird with its wide wings circling in the…