The Track displayed in this Map has elevation data associated with it, clicking on it will display an interactive elevation graph.

Minimum/maximum elevation and total length statistics are also displayed.

Customise in Settings > Misc. > Elevation Options.

A couple of things to note:

• The tracks uploaded to Waymark must already contain elevation data embedded within it, as Waymark does not look up elevations.
• Impossibly high or low (i.e. "-99999m") minimum/maximum elevations will cause crazy graphs and are caused by bad data associated with your track, not a problem with Waymark.