Treat your dog to a trip to Scotland, with its wild countryside, unspoilt beaches and miles of forest and mountain walks, it's pretty much doggie heaven. And with more holiday properties than ever now welcoming pets, there's no need to compromise on luxury and style. Take your pick from these 20 simply stunning and totally dog-friendly CoolStays, from windswept, romantic hideaways in the Highlands, to gorgeous cottages in the Borders.