Punktförmige Zugbeeinflussung
After acknowledging the warning signal the train has to stay below the braking curve (German "Bremskurve") - fast trains may travel up to 165 km/h and they must reduce the speed to below 85 km/h after 23 seconds. Note that the operation of high speed trains beyond 165 km/h is not based on visual wayside signals or PZB inductors (using LZB or European Train Control System cab-signalling instead in Germany).
High-speed rail
Railways were the first form of rapid land transportation and had an effective monopoly on long distance passenger traffic until the development of the motor car and airliners in the early-mid 20th century. Speed had always been an important factor for railroads and they constantly tried to achieve higher speeds and decrease journey times. Rail transportation in the late 19th Century was not much slower than non-high-speed trains today and many railroads regularly operated relatively fast "express" trains which averaged speeds of around .