Visited Thun castle in late June 2019. Was on our way from Zermatt area to Lucerne by train and stopped off to see the castle and walk around a little bit of the town of Thun. The castle is about a 10 minute walk from the train station and there is a somewhat little known elevator that can take you up to the entrance area that can be a nice help for someone who has issues with steps, etc. I think others have posted info on that. A bit hidden. The castle and museum were free with our Swiss Travel Pass (highly recommended, saved us so much on our vacation). The museum is located on several floors in the castle and signs lead one up thru the floors to see the exhibits. We found it nice that each level is not crammed with stuff but feels fairly open and some nice tech mixed with some pretty cool exhibits throughout. Getting to the top and the towers provides great views of Thun and the mountains beyond. The gift shop, ticket office also provides free lockers (put in 1 or 2 franc coin to lock and take key, one gets coin back when retrieving stuff) for bags, etc. as these are not allowed in the museum although one can carry phone, camera etc for taking photos. There is also a small cafe and sitting area on the main level if some people just want to hang out while others tour the castle. Was sort of a warm day but cool temps in the castle. Overall, a solid 4 star place to visit, especially if in the area and seeing a castle is on your list. Thun, the town, is also a nice place to walk around, especially along the river and near the castle with small shops and places to eat. We found the castle, short walk around town and lunch to take about 3 hours or so. A nice break on our way to Lucerne.