|two_sided = yes|
|Explicitly describes feature as two sided - applicable to for example guard rails|
|Used on these elements|
|Tools for this tag|
The two_sided key clarifies if a feature that is normally one-sided (that is, facing the right side of the way) is instead two-sided (facing both directions), such as barrier=city_wall or barrier=guard_rail (for example, when a guard rail is in-between opposite lanes).