Conflicted,
You are absolutely right, my bad, thanks for the correction, according to some research I did after your correction it seems we've been fooled! Apparently the Caspian sea is the largest lake in Asia
however as yasirkhan said, Mancher isn't worth seeing and it would be quite a mission to see the lake and be back home before sunset, I travel past it often for work as we have a project near by at Gorakh Hills and the road conditions are poor, security is poor, and the lake is also in a poor state, I would still vote for Keenjhar, I am also working on a project at Keenjhar and go there often, the tomb of Noorie is a bit of fun, lake is beautiful, and plenty of migratory birds, day before yesterday I was leaving and a huge flock of ducks flew past, it was a lovely sight.
Haris,
Keenjhar is a Ramsar site, that just means it's a protected wetland area