Where to Find and Catch Lanturn
From Pokemon Go Wiki
Lanturn are found and captured in Nest and Habitat locations.
Nests
Lanturn Nests are locations that consistently spawn Lanturn.
Habitats
Lanturn Habitats are spawn locations where Lanturn is likely to be encountered, but not guaranteed the way a Nest is.
Additional Tips and Information
Best Nests
If you know a really good nest or any of the nests above is really good, list them here:
