It was fixed it 1.8.1, but before that, there was a place called the far lands, on the edge of the map, where everything was deformed and weird, that's probably what you're thinking of.
hope i helped, have a happy christmas :smile.gif:
In beta 1.8 the strange terrain may be gone, but some of the effects aren't. After X/Z ±30,000,000 the world will start generating fake chunks. Going into the fake chunks will result in falling into the Void, and, subsequently, the player's death. If flying is used, going about 34 blocks out of the limit will cause you to be stuck, being able to use your inventory and look around, but not to move. Also, the clouds will act strangely, moving at abnormally high speeds. Reloading the save should fix the clouds, but the position glitch will still be present. Also, at excessive X/Z positions, particles (rain, water, snow, etc.) fail to appear staggered, instead forming rows of flat "panes". The Far Lands do not lag in 1.8.