A historic city in southwestern Spain, Cadiz is a popular port for European cruise itineraries that holds a very special place in my heart. It adds a more tropical flair to the traditional Spanish heritage found in most of the country.The endless tapas restaurants near the water, busy nightlife, and beautiful squares to lounge and drink espresso in create a relaxing and beautiful atmosphere. This city has the only seaport in the country and is the gateway to one of the most magical places in the world: Petra.One of the New Seven Wonders of the World, this archaeological site with temples and tombs carved into pink sandstone cliffs left me speechless. It's incredible that you can visit it via cruise ship. Although the walk into the hidden city is long and quite warm, the otherworldly ancient architecture is worth it. It may be a typical favorite for cruisers, but Santorini will always be at the top of my list.Greece is already such a beautiful country, and Santorini's remote location keeps it one of the coolest gems. Cruises anchor at sea and use tender boats to transport passengers to and from the island.The sea views from the top of the cliff are endlessly stunning, especially paired with the white-and-blue architecture. Plus the food is affordable and so tasty. Exploring Alaska should be on your bucket list. Although every Alaskan port has magnificent scenery, Skagway's breathtaking mountains will immediately capture your attention.There are small-town restaurants, a Gold Rush cemetery, and an abundance of wildlife everywhere, as well as cool experiences like dog sledding and helicoptering to a glacier. Another popular cruise port, San Juan will always hold a piece of my heart.The culture, welcoming people, and amazing mofongo (a dish of mashed and fried plantains) make this city a gem. Most cruises visit Old San Juan, but I have worked on ships that have also stopped in other nearby areas. Plus many dock at night, providing beautiful views of the fort hills and the lights of downtown.With stunning gems like Bora Bora and Tahiti, French Polynesia is probably on everyone's bucket list, but Mo'orea often gets underrated. That said, it's my favorite of the islands I've visited. The water is also crystal clear, and the lush greenery adds a unique dynamic to this paradise.From kayaking with amazing sea creatures to enjoying a drink at an overwater cabana rental, visiting Mo'orea is a dream.Situated on the North Island of New Zealand, Tauranga is a popular cruise destination when sailing from Australia.The weather usually consists of blue skies and low humidity, and there are so many great mountains to hike near the port, like Mount Maunganui.With beautiful beaches, endless outdoor adventures like New Zealand's only kayak slide, and friendly neighbors, it's my favorite place to visit on Earth — and I've been to six continents, over 65 countries, and more than 200 cities.