Invisible wall

An invisible wall. I am travelling and suddenly I cannot go any further. There seems to be an invisible wall. I am in a completely vanilla singleplayer world with no cheats and experimental features toggled off. Items on the other side of the "wall" are glitchy. I cannot place anything beyond that point ,nor can I throw a trident through. I am also in an infinite world. I am in 1.8.0. I have encountered this twice. The only way to fix this is to save and quit and then rejoin the world.