HSL 3

The HSL 3 (French: Ligne à Grande Vitesse (LGV) 3, Dutch: Hogesnelheidslijn 3, English: High-Speed Line 3) is a Belgian high-speed rail line. It connects Liège to the German border near Aachen. The line is 56 km (35 mi) long, of which 42 km (26 mi) are dedicated high-speed tracks.

The line was technically completed in October 2007; however, it did not come into operation until 14 June 2009, when ICE trains began service. Thalys trains have been using the line since December 13, 2009. The gap between completion of the line and its actual use was due to difficulties in the implementation of the safety system ETCS level 2, specifically, finding trains with ERTMS fitted.

Together with the HSL 2 and HSL 1 to the French border, the combined eastward high-speed line has greatly reduced journey times between Brussels, Paris and Germany. HSL 3 has cut Liège – Köln journey times from 1 h 23 min to 1 h 1 min. HSL 3 is used only by international Thalys and ICE trains, as opposed to HSL 2, which is also used for fast internal InterCity services.