During my daily commute from Zurich to Bern, I often noticed a big castle positioned on the Aare River. Finally, after 9 years of commuting I finally visited with a friend. This hike from Outdoor Active is a easy stroll from Olten to Aarburg, followed by a 7 kilometer hike including a 250 meter ascent to the Sälischlössli and a pass by an animal park on the way back to Olten. We included a visit inside the Festung Aarburg, an old castle which is now in use as a Jugendheim (Juvenile Detention Center) for boys aged 16-20. For this reason, visiting the castle is limited and currently, there is only one 1.5 hour tour per week on Saturdays at 14:00 (in Swiss German). It was well worth the visit.
Olten to Aarburg by the Aare River
3.8 kilometers with 50 m ascent
Aarburg to Olten via the Sälischlössli
7 kilometers with 237 m ascent
The walk to Aarburg is along the Aare by meadows, train tracks and farms.
At 14:00 on Saturdays, the Festung Aarburg is open for a guided tour in Swiss German (cost 10 CHF). The guide explains the castle’s construction history, life in the castle, how the rooms were used and a bit of how it is used today as a juvenile detention center for boys aged 16-20. The fortress, strategically located at a narrow point of the Aare River, is built into a massive spur of rock with steep walls on the outside.
The Festung is built into the rock. 
After walking in the front door, 72 steps lead up to the next level (Korinna verified). 
The castle has rooms that were dedicated to soldiers, officers, storage and defense. 
A well for water 
The barred off courtyard speaks to the castle’s current use as a detention center. 
Living space for the privileged at the top 
View from the top of the castle
After the castle visit, we continued to the Sälischlössli, a small castle with a restaurant built in 1870/71 as an expansion of a castle ruin. After the walk up, the Restaurant Sälischlössli is a relaxing place to have an ice cream (or french fries) and a great view.
Restaurant Sälischlössli 
view from Restaurant Sälischlössli 
The way home passes by an animal park. Unfortunately, the raccoons were not out but we did find some handsome deer.
