This article explains it better than I can! https://en.wikipedia.org/wiki/Irish_Travellers I was warned a few times to stay away from them, as they can be a bit rough and apparently also responsible for a lot of theft and petty crime. I liked the bunch I got to know though.
thank you for the information. I didn't know they still exist. there are some travelling roma people in south european countries but they have homes where they stay in winter.