It should be true.. At both timing the places should have lots of changes. And yes people should surely visit them at both times at least once.

Down south the landscape remains more or less the same except that it gets luser ,greener and may be cleaner during the monsoons, but mountains and high places are different and they need to be seen in all their different get ups :)

That's for sure.. Those high places will have totally different looks in winter and summer. Both must be worthy to see.

There are thousands and thousands places of tourists interest which do not change much even in high altitude, which are always laden with ice or feel snow-fall or have nothing but forests but tourists who love adventure go their for the sake of obtaining the blessings of Mother Nature who is always kind enough. One such place is Valley of flowers where I had been several times just for the sheer scenic beauty the place has on offer. Once there you would never want to come back.
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