PokeScout is the ultimate tool for finding Pokemon Go gyms

Found: The Exact Location of All the Pokémon in Pokémon Go - Atlas Obscura

Map - Pokemon GO Guide - IGN

The Best Maps for Finding Everything in Pokémon Go

Pokémon Go's maps now look a lot different - Polygon

Here's a Map of All the 'Pokémon Go' Gyms in NYC

Pokémon Go maps: Pokévision and Pokéradar maps and apps

Pokémon Go Campus Map & Guide

Pokemon Go Uploads Your Data to Google Maps

Every time I visit a new Pokemon Go gym an old one disappears from my map - here is proof (see image). Why does this happen Niantic? : r/TheSilphRoad

Top 4 Pokemon Go Nest Maps