2. You'll share new experiences with your partner. Novelty releases dopamine, the feel-good neurotransmitter. Being together with your partner when you're both out of your usual surroundings also allows oxytocin (the bonding hormone) to flow. Both of these neurochemicals played a role in the two of you getting together in the first place. Doing new things together reignites those feelings from the early days and recreates that "in love" high. This is the feeling that led you to rip your clothes off and engage in passionate lovemaking as often as possible. Being on vacation creates the opportunity to return to those glory days.
3. You get to spend one-on-one time with your spouse. Intimacy isn't just a physical phenomenon. It is emotional, mental and spiritual as well. "Getting busy" is just one aspect of intimacy, although it's the one that's easiest to quantify. True intimacy involves sharing your whole self with each other: your thoughts, dreams, and fears, as well as your bodies. When you're on vacation, you have time to engage in deeper conversations, during which this intimate sharing takes place. The two of you are replicating those dating behaviors that became the foundation of your relationship. You have the time to go past your standard informational exchange to really talk on a more personal level. This creates an atmosphere of closeness that naturally leads to physical intimacy.
Couples always want to know if it's possible to still be in love after years together. Taking couples-only vacations on a regular basis is one of the best ways to do that. It keeps you connected and your sex life humming.