I’ve heard that there is a gezeira not to spend the night in York. Is this true? What’s the reason?
This is the accepted tradition and practice handed down for many generations among the Jews of England. The reason given is because of he massacre that happened there in the year 1189 during one of the crusades. The gentiles of York attacked the Jews of York, and although they ran to hid in a fortress they were still all killed out. According to one opinion, if there is a need to go there, we can’t say that halachically it is prohibited.
Leket Shailos Metzuos – 4 pg. 120.