I'm planning to make an adventure map out of this with a city of each biome (Mountains, snow, jungle, forest etc.)
It's a classic superflat world 'cause in the beginning I Wasn't planning to start an adventure map.
It's really not far and I would like to get some help.
So far it includes a Hidden Temple with an End-Portal.
A small Wooden Fortress known as Trordonia
A small Starting House.
And a City in the Trees (REALLY small).

BTW: There are a few secret hallways going underground leading from Trordonia to City in the Trees to the Hidden Temple.