None of the info either on-line, or in HSB publicity, note the bargain 18 Euro 3 day pass which is currently on offer. This may be an out of season only deal. It covers the entire HSB network, with the exception of the Brocken, all the buses in the Harz region and local towns, and all the trains within the region run by HEX, the local operating company. A trip up the Brocken also allows for a 50% discount on ay other route taken within a week, but it needs to be purchased at the same time. However, any long trip on the HSB costs more the 18 Euro 3 day ticket, so it's worth buying just for a day's visit. It's hard to work out exactly what the deal involves, since none of the HSB staff speak English.