>> I want to know about tissot first cliff walk in Grindelwald ... Heard from other tourists about the cliff walk.is it too scary?
If you don't have a problem with heights, it is exciting rather than scary. It is perfectly safe. The walkway has a metal-grille surface, which you can see through, and handrails. There is a slight decline at the start, then the rest is level, and there are no steps. You do have to duck a little to get round one or two rocky outcrops. It only takes about 10 minutes at a leisurely pace, and you can return the same way.
>> cost? ( I have 8 days swiss Travel pass consecutive)
The cliff walk is free. The bus in Grindelwald is free with the Swiss Travel Pass and you get 50% off the gondola from Grindelwald to First.
>> special precautions?
>> How to reach?
Starting from Grindelwald railway station, walk up the main street (Dorfstrasse) for 10 minutes or so, or else get Bus #121, #123 or #128 to the bus stop called "Firstbahn" (second stop from the station). From the bus stop, cross the road and walk a short distance uphill along a lane between shops to the First gondola valley station.
The start of the cliff walk is adjacent to the restaurant terrace at the top station of the gondola. There are two mid-stations before you get to the top: Bort and Schreckfeld, but you can stay in the same gondola all the way.
>> can I manage it with Jungfrau in one day?is it possible to do the cliff walk and then continue train journey to to Jungfrau top?
Yes, but if I were you, I would go to the Jungfraujoch first if the weather is clear in the morning. If you leave it until the afternoon, you might find the clouds have rolled in and blocked out the views - so that will be the end of that!
I suggest you go up to Jungfraujoch in the morning via Lauterbrunnen/Wengen, and return via Grindelwald. If you catch the 13:13 or 13:43 trains down from Jungfraujoch to Grindelwald, that should give you enough time to spend 1-1.5 hours up at first. The last gondola down from First is at 17:30.
You can plan in detail with the Swiss Timetable:
I have attached some photos of the cliff walk taken in September and December last year.