It's difficult to determine the least car-friendly city in Europe, as many cities have implemented measures to reduce traffic congestion and encourage the use of public transport, cycling, and walking. However, some cities are known for having more challenging driving conditions and restrictions on cars than others.

One city that has been noted for its limited car access and high congestion is London, England. The city has implemented measures such as congestion charges and low emission zones to reduce traffic, improve air quality, and encourage the use of public transport. The congestion charge, which is a daily fee to drive in central London, has been in place since 2003, and low emission zones have been introduced in recent years, which restrict older and more polluting vehicles from entering certain areas of the city.

Other cities in Europe that have implemented similar measures include Stockholm, Sweden, which has a congestion tax, and Milan, Italy, which has implemented a congestion charge and limited traffic zones in the city center.

These measures have been put in place to reduce traffic congestion, improve air quality, and promote sustainable modes of transport. While they may make it more challenging to drive a car in these cities, they have also contributed to making them more livable and environmentally friendly.