Available with 3D Analyst license.
- Right-click the terrain layer in the table of contents and select Properties.
- Click the Symbology tab.
- Uncheck Elevation (or any other face renderer that is checked).
- Click Add.
- Click Edge type grouped with unique symbol.
- Click Add.
- Click Dismiss.
- Click Edge types in the Layer Properties dialog box.
- Click Add All Values .
- Click OK
By default, only the type 1 and 2 (soft and hard) edges are displayed.