It confusing since we don't know exact story time from Eren first reveal till reclaiming the wall
I'm more wondering lack of trouble from wall 3 to wall 4 considering previous survey squad didn't know of the ocean
Granted they could have been mind wiped
This is one thing I have been thinking about as well. They must have gotten quite far outside the wall while Wall Maria was still in their possession, and even tried to establish bases and such.. I guess the best explanation would be that it's quite far between Wall Maria and the ocean, and that the huge amount of titans on the outside ultimately killed everyone who got close. Still doesn't make much sense, since I believe even counting only the size of Wall Maria, Paradis Island would be almost the size of Germany, and if we add all this new distance, it would become ridiculously big for an island, more like a continent tbh, which doesn't make sense when you look at the island on a map next to Marley.. Not to mention why the King of the wall would allow the Survey corps to go outside and possibly find the ocean again after all the trouble of wiping all memories of it from the population.
Like you say though, it may be that the King simply used the coordinate to make humans forget to ocean once it was discovered.
Edit: According to information given in the first Attack on Titan episode, as well as in the official guidebook, the area within the wall is as much as 720,000 square kilometers. Which would be about two Germanys, or one Turkey. Within the walls.
Edited by diezdragon, 10 February 2017 - 09:56 AM.