In the summertime, the ski fields around Oslo turn into miles of picturesque hiking trails. If you catch the T-bane (metro) from the centre of the city all the way to the end of the line at Frognerseteren (the journey itself is very beautiful), you will be deposited at a restaurant clinging to the side of the mountain with a spectacular view over Oslofjorden. From here, you can pick from a variety of walking tracks that will take you back down the mountain and which usually finish at another metro stop. We chose to do a loop (maybe 10-15km) which ended at Sognsvann lake, the home of the Norwegian Olympic Sports Centre as well as another conveniently placed metro stop on a line that took us directly back to our hotel in the centre of the city. All in all, it’s very easy to make a day of it! Just remember to bring some warm clothes in case the weather turns bad, although it seems we were exceedingly lucky on this day, and maybe buy some snacks from the restaurant before you set off on your trail.