The Valentin bunker is a historical landmark that served as a submarine shipyard for the Nazi regime during the Second World War. It's the largest bunker in Germany, not to mention that it was one of the largest armaments projects of the Nazi era. Today, it's a memorial site which includes exhibits of eyewitness statements, historical photos and other information about the lives and conditions endured by the labourers once forced to work here. You can visit the bunker on your own or join a guided tour.

Simply put, Iceland’s famous Golden Circle is a popular route between three of the island's most visited attractions. Usually done as a day trip, the route starts in Reykjavik and takes you south and inland, to the Þingvellir National Park. There you enter the Geyser geothermal area with the Strokkur Geyser being most eager of the bunch. Finally, you arrive at to the 32-metre tall Gullfoss waterfall in the canyon of the roaring Hvítá river. Many tour agents and travellers themselves like to make extra stops along the way to see a geothermal power plant or spend a few hours at one of the spas. You could rent a car and drive between the landmarks at your own speed. In summer, you could even use the long daylight hours to avoid the crowds that tend to come earlier in the day. If you can pick your own route, don't miss the Kerid Crater Lake — a scenic lake that occupies a 3,000 years old volcanic crater that you can easily reach on foot.

The Blue Lagoon is without a doubt the most well-known geothermal spa in Iceland. The signature milky-blue water makes a stark contrast to the surrounding black lava fields and creeping grey moss. The spa is located in a lava field near Grindavík and is supplied by water used in the nearby Svartsengi geothermal power plant. The water temperature stays at 39°C year-round, snowfall or sunshine. Most visitors make the spa their first or last stop, since it's conveniently located only 15 minutes from the Keflavík International Airport (and around 30 minutes from the capital city). If you are buying a tour, it makes most sense to combine the spa visit with the Golden Circle day trip.

The festival is regarded as the biggest celebration of music in Iceland and boasts an unrivalled line-up of established and up-and-coming artists.