→Introduction: Add example of I-10 & I-17
Seagulling is the editing practice of changing the elevation of one segment as it crosses immediately over/under another segment. This is not necessary and does not serve any navigation purpose. Elevations are used to delineate the crossing segments so they do not create a routing problem. Instead of cutting a segment into small pieces to accommodate the elevation change, it is better to leave the entire segment at the desired elevation.
In Arizona, all primary freeway segments are set to Ground elevation, unless they cross another freeway segment, then one will either be +1 or -1 elevation.
== State Highway Naming ==