Actually we just wanted to refill some water, but our paladin tripped and fell into the water. He was lucky in that he noticed a small passage in the water that led to a hidden cave that could be reached by squeezing through.
The small lake there had a narrow bank on which lay the remains of an ancient corpse, with old leather armour still hanging in tatters. It lay next to an unopened treasure chest.
In the corner lay a small nest with an egg.