The Island of Hawaii (i.e., the Big Island) contains 10 of the world’s 14 climate zones — the only spot on the planet with so many condensed into one small region. Lush tropical terrain rules the green, wet, windward side of the island (see Akaka Falls and Waianuenue/Rainbow Falls), while more arid beauty is on display at Hapuna Beach Park. You can even enter an ice climate at the mystical summit of Mauna Kea volcano, as well as Lake Waiau, one of the highest lakes in the United States.
Can you see all the major sights in Athens in one day? No. But you can see the Acropolis, Acropolis Museum, and the top historical sites of the Plaka in one day. If you had an extra half-day then visit the Archaeological Museum in Exarcheia. That still leaves many great sights but you will have seen all of the iconic Athens attractions. Adding Naxos is always a good idea. You might even enjoy it more than Mykonos (but no nightlife like Mykonos).
Lefkada is the island that’s not an island. You can drive to it across the causeway from the mainland, but it feels every bit an island. Aristotle Onassis bought the satellite island of Skorpios here as his own bit of getaway paradise. Beaches, windsurfing, boat hire, good food and wine are all here and there are few built-up package resorts. The main tourist area is centred on Nydri.
Hawaii’s biggest island has everything you could ever want to do and more. But what separates it from the other islands is Volcano National Park. Explore volcanoes, climb through old lava tubes, and watch as new lava oozes into the ocean. Then there are all the waterfalls on the island, too. Big Island has it all. I mean it’s Hawaii — how could you go wrong?!
Since airline reservation requests are often made by city-pair (such as "show me flights from Chicago to Düsseldorf"), an airline that can codeshare with another airline for a variety of routes might be able to be listed as indeed offering a Chicago–Düsseldorf flight. The passenger is advised however, that airline no. 1 operates the flight from say Chicago to Amsterdam, and airline no. 2 operates the continuing flight (on a different airplane, sometimes from another terminal) to Düsseldorf. Thus the primary rationale for code sharing is to expand one's service offerings in city-pair terms to increase sales.