oneway = no
Legal oneway restrictions for a mandatory direction of travel for boats on 水路也可以被标记为单向，for instance when signposted with a seamark or when this is part of legislation。水流方向通常被路径方向定义。当遇到有两个水流方向的地区的特殊案例时，请考虑与oneway=不同的标签，毕竟oneway=描述了法律意义上的通行方向而不是物理意义上的水流方向。
- oneway=reversible - 很少但规律地在两个方向上变化的道路。这个标签可以在如Zh-hans:Conditional restrictions页面上解释的情况使用。
- oneway=alternating - 经常并规律地在两个方向上变化的道路。
This assumes that oneway restrictions do not apply to pedestrians. This in in line with the meaning of common one-way traffic signs, such as sign C, 1a in the Vienna Convention on Road Signs and Signals ("entry is prohibited for all vehicles").
Note that even on a formal highway=footway (with a "footway" traffic sign that in general means that vehicles may not enter, such as D, 5) some vehicles may still enter; for instance when certain types of vehicles (such as bicycles) or certain groups of road users (such as destination traffic) have been exempt from this prohibition by an additional panel. Even in such cases oneway=* may not apply to pedestrians but only to vehicles.
Although unusual, oneway on pedestrian highways (path, footway, track) is possible in some countries. While it is sometimes represented with the disputed tag: oneway:foot=* it has been argued that the tag foot:backward=no should be preferred, as it doesn't suffer from the problems of the former. In the past highway=path + oneway=yes was used by some mappers to mark that pedestrians may move only in one direction, these situations should be corrected, as oneway in OSM only applies to vehicles. Furthermore a highway=path may be open to others road users such as cyclists.
Not all current usage reflects the above theory. For example, in late 2021 highway=path+oneway=* used on 32000 (out of total 72000) objects, oneway:foot=yes on 550 (out of 2200 total oneway:foot=* objects, mainly used as "oneway=yes+oneway:foot=no") and foot:backward=no on 110 (out of total 260), showing that some mappers consider oneway=* valid for all kinds of movement, including foot. On the other hand, there is a massive number of one-way streets tagged only with oneway=yes which are bidirectional for pedestrians. Data consumers could follow the vehicle-only theory in most cases but pay special attention and possibly deviate from that theory if oneway:foot=* is present or if oneway=* is set on a footway. Of course, data consumers may always decide to interpret tags however they deem suitable.
Cases of oneway pedestrian traffic includes some hiking trails - some permanently, some during the high season crowding, border crossing, exit-only passages and more. Mandatory oneway traffic for pedestrians also has been used as a measure for social distancing against COVID-19.
The following table lists country-specific information needed for correct interpretation of oneway tags.
|Country||Country-specific implications of oneway tags|
|Netherlands||Oneway restrictions apply not just to vehicles, but to "voertuigen, ruiters en geleiders van rij- of trekdieren of vee". In OSM context, this e.g. means oneway=yes implies not just vehicle:backward=no but also horse:backward=no (unless oneway:horse=no).|
|United Kingdom||Oneway restrictions also apply to horse riders. In OSM context, this e.g. means oneway=yes implies not just vehicle:backward=no but also horse:backward=no (unless oneway:horse=no).|