I had a similar experience to Iqbal a few years ago in Malawi. My wife and I were driving our Land Rover down a dirt track when we came upon a span of track that was flooded. There were some small kids midway out standing in water to their knees, so we figured it wasn't very deep. As I drove into the water we suddenly plunged down to the hood half way towards the kids! It turned out that they were standing on a rise in the track...

Having estimated that it was much more shallow than it turned out to be, I was driving with too much speed to create a perfect bow wave in front of the radiator (which is important when wading with vehicles in deep water). Thus the wave not only splashed up the hood, but in fact splashed all the way up the front windshield up to the roof!

This lasted luckily only a couple of seconds before the Defender was on a more shallow part of the flooded track.

Just by chance the side windows were up at the time, or else we would have filled the car with water.

On the bright side, the car, and especially my windshield was cleaner than it had been in months.