may i know how to travel from venice to st moritz switzerland?possible by night train..how is the route..how much the price..i'm travelling in six pax.

you can check schedules on the Italian train system website, www.trenitalia.com or the German train system www.bahn.de, or sbb.ch (Swiss). I don't know if you'll be able to see prices for this complicated route.

It's not a route that would be easy to do on a night train, as you'd need to take 3 different trains + a bus, for 4 different legs each of ~2hrs each.

First, for schedules only, use a capable quick all-Europe online timetable at www.bahn.de. But being German Railways, this won't give fares or sell tickets.

www.trenitalia.com WILL sell tickets, but probably only for Venice-Milan-Brig, probably not for the whole trip, so you'd need to buy an onward ticket at Brig (not a problem!). If it won't cope with Venice-Brig, book Milan-Brig then Venice-Milan allowing at least 45 minutes in Milan to change trains.

Trenitalia.com accepts (I guestimate) 60% of UK credit cards but only 20-30% of US ones, that's the catch.

There are no night trains between Italy & Switzerland any more.

Only one practical way - Venice to Milan, change to the sideline that terminates in Tirano, Italy - hop out the station front door and go cater-corner to the Swiss train station a few yards away - then hop on the hourly or so trains that go up and over the Bernina Pass to St Mortiz.

BTWi have riddent this route - the Bernina Pass several times and i consider it by far the most awesomely scenic train in Switzerland - and the only one to go up and over the Alps and not burrow under them, north to south that is - a Top of the World scenery - glacial lakes - glaciers, etc.

A great way to go between Italy and Switzerland. The scenery between Venice Mestre and Milan really sucks and that to Tirano is so so but it does go by Lake Como a tad.

If you use Pal's suggested route (which is also my own) you might want to consider taking the earliest possible departure from Venice to Milan; the timings from Milan-Tirano run about every two hours or so (no need for reservations on this mostly 2nd Class regional).
As Pal has indicated, the change from Trenitalia to the Rhaetian Railway station in Tirano is quite simple..the stations are only a few yards from one another.

The route Milan-Tirano will take you up the east side of Lake Como between Lecco and Colico and that is somewhat scenic in and of itself.
The Bernina Pass route up to St. Moritz is nothing short of spectacular scenery and depending on the timing you may or may not have to change trains in route.

I honestly don't think it is possible to do this overnight and IMO you shouldn't since you would miss the views.

It will be a LONG day but worth every minute of your time IMO.