Hiking / Walking
Rütli
The Rütli is the place where the old Swiss Confederation was founded. The walk takes 60 min one way. You can add the boat trip from Rütli to Treib and take the cable car back to Seelisberg (or other way round)
The path of Switzerland
This path was built to the 700 year anniversary of Switzerland. You will find a good overview here.
https://www.erlebnisregion-mythen.ch/de/erlebnisse/sommer/weg-der-schweiz/
Klewenalp Stockhütte
Gondola ride, hiking, biking, etc.
https://www.klewenalp.ch/de/informationen/broschueren/
Niederbauen
Gondola ride from Emmetten
Alp Weid
Gondola ride from Seelisberg
Attinghausen Brüsti
A nice place to spend a day in the mountains
http://www.attinghausen-tourismus.ch/seilbahn-skilift/attinghausen-bruesti/
Arnisee
Visit this nice little lake, option of two cableways
Bannalp
Rickenbach
You can start in Beckenried with a gondola ride to the Klewenalp, walk to Maria-Rickenbach, go down with the gondola, take the train to Stans and take the bus back to Beckenried where you started
Stanserhorn
The Stanserhorn is a great place for hiking or just take in the spectacular view. It has an oldtimer funicular, the world's first CabriO cable car and a revolving restaurant.
Pilatus
Great different opportunities to reach Pilatus from two sides. A lot of activities (e.g. rope park)
And many many other scenic places where to spend the day out.
Find more on https://www.myswitzerland.com/en-ch/home.html