Create a Multi-layer Map in Drupal 7 with Openlayers 2.x
There are many tutorials out there for creating maps in Drupal but most of them focus on just one layer on a map. This tutorial is for creating one map with multiple, switchable layers complete with pop-ups and a title. This tutorial covers creating a primary map based on one main content type and also adds an additional layer for a user's profile. This is a lengthy but thorough tutorial and I'll try to add images or a video at some point soon. The basic premise is this: A content type with two complementary fields pass address data to Openlayers which displays those maps on a Views page.