If longevity is a sign of quality, then Crieff Hydro Beauty Salon, a historic retreat that’s been tending to spa seekers since 1868, should sit at the very top of the spa tree. The view of the pool is worth the visit itself. Retaining its architectural charm, it boasts glorious ceiling paintings to ensure your backstrokes come with quite spectacular views. The treatment menu, likewise, isn’t bog standard. It is marked out as a Clarins Gold Salon, featuring four deluxe therapy rooms, plus it’s the first spa in Scotland to offer the expert Temple Spa range.