lit after sunset until sunrise, or in case of bad visibility also during day time. Blinking lights are allowed with a minimum frequency of 120 flashes per minute (2 Hz). Blinking orange front-facing lights are not allowed (due to possible confusion with vehicle turn signals). All bikes sold since 1988 must have brakes on both front and back wheels. See also Bicycle monarchy Danish National Cycle Routes Cycling in Copenhagen Outline of cycling References External links Making the Bike as Logical a Choice for Commuters as the Car, Bus, Train or Metro November 12, 2012 Transport in Denmark Urban planning in Denmark