Depending on what kind of tour guide you are and where you work, you may have the opportunity to take people to see wildlife. You get to see the same sights through new eyes, and you can share your expertise with them.
If you get hired by a big company, then you may be able to transfer and work abroad. Being a tour guide is not easy, though; you'll have to deal with customers, be ready for any emergency, and be extremely knowledgeable about the area.
To become a tour guide, there are schools you can attend to get certified, though that's not necessary.