How to get to Gnome Memorial Mountain
Gnome Memorial Mountain was added into the game during the 20th Anniversary and during The Burning Lands expansion. In order to get to this zone you'll first want to head to Dragonscale Hills, the Secrets of Faydwer zone. You can reach DSH by taking the Guild Hall portal or having a Wizard/Druid port you to this zone.
Once in Dragonscale Hills you will want to travel down to the south-central portion of the zone near the southern most docks. Here you'll find a mechanical machine (shown in the screen shot below) that will launch you into Gnome Memorial Mountain.