Some "highway" tag values attempt to convey information about the importance of the road in question. Such commonly used values include "motorway", "trunk", "primary", "secondary", tertiary" and "unclassified". There is evidence that this classification is not a universal system. Below is an attempt at collecting information on how different regions classify their roads. It might provide an insight into how a more unified system might work.
Please note that unlike Highway:International_equivalence, we are trying to explain what individual classes mean in our countries to each other, so keep it in English and try to explain the system to someone who has no idea of what your roads are like.
Officially, roads are divided into "motorways" [dálnice], "highways" [silnice], "streets" [místní komunikace] and "service roads" [obslužné komunikace].
Streets are maintained by the municipality and are divided into four classes. The first three roughly correspond to highway classes while the fourth is mostly highway=footway|pedestrian|living_street etc.
Highways are divided into three classes:
- 1st class - Long distance and international transport, includes motorroads, owned by the state.
- 2nd class - Interregional transport, owned by region
- 3rd class - Connecting municipalities, owned by region
The system is widely known and used. Road class is reflected by signage and ref numbers. A rough idea of road character can be gained from the class alone.
Anything above a third class is virtually guaranteed to be paved and so are many third class roads.
Shares ref numbers with 1st class, prefixing them with D. Relatively strict construction requirements. Access restricted to motor vehicles with top speed of at least 80km/h. A coupon must be bought for vehicles under 3.5t. Vehicles above 3.5t must be equipped with an electronic toll paying system.
Currently tagged as "highway=motorway"
Motorroads [Silnice pro motorová vozidla]
Technically part of 1st class. Only motor vehicles allowed. Often close to motorway standards.
Currently tagged as "highway=trunk" "motorroad=yes"
Some selected sections of 1st class roads that are close to being motorroads. Radials, bypasses and short, already completed sections of future motorways often fall into this (mostly informal) category. At least 4 lanes can be expected.
Currently tagged as "highway=trunk" without "motorroad=*"
1st class [Silnice první třídy]
71 roads for long distance and international transport. Up to two-digit ref numbers, often written as I/##. Sometimes 4 lane. Almost always designed for at least 70km/h.
Currently tagged as "highway=primary"
2nd class [Silnice druhé třídy]
Roughly 450 inter-district roads. Three-digit ref numbers, often written as II/###. Design speed of at least 50km/h.
Currently tagged as "highway=secondary"
3rd class [Silnice třetí třídy]
Local network roads. Occasionally designed for less than 50km/h and even as single lane. Ref number consists of four or five digits. Written as III/#####, but rarely seen.
Currently tagged as "highway=tertiary"