Deutsche Bahn (www.bahn.com) and FlixBus (www.meinfernbus.de) each operate daily services to Berlin via Magdeburg. Prices fluctuate and schedules change, with FlixBus often having the cheapest fares and some direct services; check the websites for details.
Südniedersachsenbus (formerly Regionalbus Braunschweig and managed by Deutsche Bahn, just to confuse) operates services throughout the Harz region; use the easy online route planner for fare and timetable searches.
Car & Motorcycle
The B6 runs north to Hildesheim and east to Bad Harzburg, Wernigerode and Quedlinburg. The north–south A7 is reached via the B82. For Hahnenklee, take the B241.
Bad Harzburg–Hanover trains stop in Goslar, as do most trains on the Braunschweig–Göttingen line. There are direct trains to Wernigerode (€11, 40 minutes, every two hours) but services to most other destinations require changing trains in Vienenburg.