Do you like adrenaline and you are not afraid of heights, then this suspension bridge might be for you. I only been in winter which is extremely impressive but you can visit Titlis Cliff Walk all year.
How to get there: Take the cable car from Engelberg up to Titlis. You need to change in between into the Titlis rotair. On top you can visit the cliff walk suspension bridge and a Glacier Cave. In Winter you can also visit the glacier park for some more fun activities.
Price: Its 69chf return with the half fare/swiss travel pass and 96chf return on a regular base.
Tip: Try to take the last cable car back down around 17h. Go to the bridge and the cave around 16h-16.30h and you will have both for yourself like I had.