marking shared bus/cycle lanes. Colombian city, Bogota converted some car lanes into bidirectional bike lanes during coronavirus pandemic, adding 84 km of new bike lanes; the government is intending to make these new bike lanes permanent. In the US, slow-street movements have been introduced by erecting makeshift barriers to slow traffic and allow bikers and walkers to safely share the road with motorists. Traffic reduction Removing traffic can be achieved by straightforward diversion or alternatively reduction. Diversion involves routing through-traffic away from roads used by high numbers of cyclists and pedestrians. Examples of diversion include the construction of arterial bypasses and ring roads around urban centres. Indirect methods involve reducing the infrastructural capacity dedicated to moving motorized vehicles. This can involve reducing the number of road lanes, closing bridges to certain vehicle types and creating vehicle restricted zones or environmental traffic cells. In the 1970s the Dutch city of Delft began restricting private car traffic from crossing the city center. Similarly, Groningen is divided into four zones that cannot be crossed by private motor-traffic, (private cars must use the ring road instead). Cyclists and other traffic can pass between the zones and cycling accounts for 50%+ of trips in Groningen (which reputedly has the third-highest proportion of cycle traffic of any city). The Swedish city of Gothenburg uses a similar system of traffic cells. Another approach is to reduce the capacity to park cars. Starting in the 1970s, the city of Copenhagen, where now 36% of the trips are done by bicycle, adopted a policy of reducing available car parking capacity by several per cents per year. The city of Amsterdam, where around 40% of all trips are by bicycle, adopted similar parking reduction policies in the 80s and 90s. Direct traffic reduction methods can involve straightforward bans or more subtle methods like road pricing schemes or road diets. The London congestion charge reportedly resulted in a significant increase in cycle use within the affected area. Traffic calming Speed reduction has traditionally been attempted by statutory speed limits and enforcing the assured clear distance ahead rule. Recent implementations of shared space schemes have delivered significant traffic speed reductions. The reductions are sustainable, without the need for speed limits or speed limit enforcement. In Norrköping, Sweden, mean traffic speeds in 2006 dropped from 21 to 16 km/h (13 to 10 mph) since the implementation of such a scheme. Even without shared