This. A lot of posters on here will only have been to games in the all seated era.
Before this, you went through a turnstyle into a narrow concourse with a few dark tunnels heading to the terraces, you had no idea how busy that pen was until you got into it. There were fences at either side and at the front to stop you getting on the pitch. You were literally penned in. If the pen you went into was too busy you had to come out the way you came and go in the next tunnel