Hawaii’s most famous landmark, the Diamond Head, is a volcanic crater with a 360-degree view over the island, and its name comes from English sailors who thought its calcite crystals were pure diamonds. The scenic hike up to the summit, taking the so-called stairway to heaven, will not be soon forgotten, and so it happens to the views from atop.

This museum tells the story of the Nazi occupation of Krakow during World War II. It is located in the former administrative building of Oskar Schindler's factory. A guided tour is available, but you will also find detailed explanations in English around the museum.

While in Cologne, you can visit Germany's oldest city hall, with parts dating back to the 11th century. Over time, it has picked up a mix of styles—Gothic tower, Renaissance loggia, some modern touches. The 61-metre tower is covered in carved figures, including some cheeky ones from local history, and the bells chime four times a day. There’s also a mechanical face called the Platzjabbek that sticks its tongue out on the hour. Inside, the Hansasaal is the main historic hall—worth a look if it’s open.

Thacher Hall, built in the mid-1800s, is a beautiful historic building in Yarmouth Port. Constructed by the Yarmouth "New Church" Society, followers of Emanuel Swedenborg's theological teachings, the hall is an example of the New Church movement's influence in the region. The building is now overseen by the Yarmouth New Church Preservation Foundation, which is dedicated to its restoration and preservation.