During special events held on Eldemore you are able to browse through the map in the Explore section on the red head bar on top of the page. When you hover above it, it should look like the following example screenshot.
Once you are on the main map, you can discover the land of Eldemore on your own by a simple click on the little map icons. Be sure to check back every event if a new location was added.
When you hover above one of these icons they should start to glow a bit like in our following example screenshot. Also a smal box with some informations will pop up and explain you what this location is about.
Once you've found the location of the current event you can start to explore it. During those events you are able to visit new places or revisit old ones but in a very new and totally unique look. Every event is held on one spercific place. If you go to the other locations during an event it might appear that the little text below the location image is changed, like in the festival of lights event.
If you finished to explore the other places you might should come back to the location of the current event. Now you can go to collect tokens and special pile pets from a very special place, found on every event location page. And if you collected enough tokens you can go and swap then to get rare pets.
How to adopt event pets is explained more brifly right in this tutorial.