Naked People and the Cow level

Okay, so I'm going about my business doing quests and stuff and I travel to charing cross station maybe thirty minutes ago. I bunch of people had almost no armor on (I think the most I saw were shoulder pads) and they were just spamming the party portal. Saying it was the way to get to the cow level. I'm pretty gullible so I wanna know if this is for real, and if it isn't bs how do I do it? Thanks to anyone who can answer this question.|||i dont think so.... but then again i could be wrong