On Sunday you can sign up for the activities 1 and 2 on Tuesday afternoon:
1. Glacier Canyon Grindelwald:
https://outdoor.ch/de/outdoor-activities/gletscherschlucht-grindelwald/
2. Take the cable car up to First to enjoy:
- First Cliff Walk – open till 3:30, https://www.jungfrau.ch/en-gb/grindelwaldfirst/first-cliff-walk-by-tissot/
- Short hikes
- Or take the scooter downhill: https://www.jungfrau.ch/en-gb/grindelwaldfirst/trottibike-scooter/
3. Visit the top of Europe (note that it takes 90 min from Grindelwald to get there):
Disclaimer: please have a careful look at the weather and dress accordingly: https://www.meteoswiss.admin.ch/local-forecasts/grindelwald/3818.html#forecast-tab=detail-view
Alternatively the Sunstar Hotel offers a great wellness area: https://grindelwald.sunstar.ch/en/wellness/
