Minecraft 1.7, dubbed “The Update that Changed the World”, was released in 2013 after the pointless 1.6 update. Its changes to terrain demanded a new world or facing sudden, jarring cliffs and oceans as the old meet the new in old worlds.
I did a lot of wandering around in this world without much building. At first. A few weeks later, YouTuber Tango Tek released The Iron Foundry. All that Iron blew my mind. I needed it.
I eventually finished the Iron Foundry myself, and even made a really swanky Minecart system that collected the iron and transported it directly to me. I always really enjoyed redstone circuitry and this proved to be a fun challenge!
With that, I wanted to really work on my base. The first obstacle was caves hidden under tall grass. I covered all of them up with a trapdoor and torches indicating if it was fully explored or not. The next challenge was, of course, hostile mobs spawning at night. So I naively lit the entire area around my base… and then absolutely hated it! Enough to quit the world entirely. The end.
This world did not last very long, unlike my 1.4 world (or any of the earlier ones). Probably for the best, as the next update (1.8) broke the Iron Foundry.