The North Sea coastline has low and high tides and you can see it is low tide here.
You can walk in a way on the bottom of the sea which has made waves in the sand, watch the little footsteps of the seagulls.
And the big steps of men.
The tide was coming up when we were there, we saw the sea coming closer to the beach. The sea was very calm and flat yesterday, but it can be very raging with dangerous high waves.
For these little toddlers the undeep sea is a nice playground.
On the horizon we could see big ships sailing maybe to the UK or Germany.