Every resort in this feel-good age must have a spa. It’s no longer an option. It’s an essential amenity. But how many resorts can lay claim to natural mineral springs like this week’s PGA Tour host, The Greenbrier? Interestingly, many of the oldest and most historic resorts in North America and Europe sprang up after the discovery of a healing, therapeutic spring. In turn, many of the oldest and most venerable golf courses are attached to often-remote resorts that were founded to accommodate travelers who wanted to “take the waters.” Most made the journey to relax, unwind, or even cure themselves of an ailment, not including the yips, the shanks, or duck hooking. Here's guide to golf and grottos.