You can use the Elevation Marks On/Off tool to display elevation marks in your 2D plan view. An elevation mark contains the label given to the elevation in the elevation’s properties, as well as a target arrow that identifies the view direction of the elevation.
By default, four marks are displayed, one for each of the default elevations on the Elevation View menu. If you have created a custom elevation, a mark is displayed for that elevation as well.
To turn elevation marks on or off:
Select View > Viewing Aids > Elevation Marks On/Off, or
Click the Viewing Aids button
on the Basic View Control or Advanced View Control toolbar and select
Elevation Marks On/Off
The marks are located at the extents of your drawing, so you may need to zoom out to see them.
If you select and right-click an elevation mark, you can access a number of editing tools such as Properties, Move and Move Target. Selecting View Elevation displays the elevation associated with that mark.