Down by a shining water well
I found a very little dell,
No higher than my head.
The heather and the gorse about
In summer bloom were coming out,
Some yellow and some red.

I called the little pool a sea;
The little hills were big to me;
For I am very small.
I made a boat, I made a town,
I searched the caverns up and down,
And named them one and all.

And all about was mine, I said,
The little sparrows overhead,
The little minnows too.
This was the world and I was king;
For me the bees came by to sing,
For me the swallows flew.

I played there were no deeper seas,
Nor any wider plains than these,
Nor other kings than me.
At last I heard my mother call
Out from the house at evenfall,
To call me home to tea.

And I must rise and leave my dell,
And leave my dimpled water well,
And leave my heather blooms.
Alas! and as my home I neared,
How very big my nurse appeared.
How great and cool the rooms!

Robert Louis Stevenson

http://www.poemhunter.com/poem/my-kingdom-2/