The Bernina Express trains have bigger windows and the name but the regular red trains have fewer people and travel the same line. The sites are magnificent but don't lean out the window too far - it's straight down in places.
The train travels relatively slowly allowing lots of time for pictures and in the regular train you can probably go from side to side to take picture - unlike the packed cars where all the seats are full.
The is a great trip and the only way to see it "hands free" is by train!
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