What and where is the Mountain of Butterflies? Here is the incredible story of a decades-long search

In 1975 a search that has spanned several decades finally came to fruition when volunteers discovered the overwintering place of the monarch butterfly

One of the natural world's most fascinating mysteries, the Mountain of Butterflies, was unlocked 41 years ago today.

The discovery of the overwintering place of the graceful monarch butterfly had taken several decades of searching by thousands of volunteers.

But after trekking across an entire continent for an answer, it was a team led by Canadian zoologists led by Fred Urquhart that final tracked the resting place of the butterflies as they made their migratory journeys south

.Ken Brugger and Catalina Trail's determination helped the team find the answers they had been looking for.

The butterflies attach themselves to oyamel trees in the Sierra Madre Mountains, in eastern Mexico.

The monarch butterfly is under threat due to climate change and deforestation in the country, where the species migrates to from the the US and Canada in winter.

The discovery has been celebrated today by a Google Doodle on the search engine's homepage.

The homage to the discovery was created by artist Kevin Laughlin.