@jrplus You'll need to either host or have some other means to get the mapping tiles/layers. We have blogpost on getting started for that located here: https://www.elastic.co/blog/custom-basemaps-for-region-and-coordinate-maps-in-kibana.
The long story is that Kibana acts as a gateway to the Elastic Maps Service, and without a "hot" internet connection to load this information, you'll need to supply it by some other means.