In a previous post we showed you how you could connect directly to ArcGIS Online from ArcGIS Explorer to view additional content found there.

Another interesting service is the Operational Navigation Charts (ONCs). This service presents a digital version of the charts at 1:1,000,000-scale. The ONCs were produced by the US National Geospatial-Intelligence Agency (NGA). The map includes over 200 charts across the world, excluding parts of North America, Europe, Asia, and Oceania where charts are not publicly available. Here's what the coverage looks like:

Connect to ArcGIS Online like we described in our earlier post and open the Specialty folder. Choose the EVC_Topo_World globe service.

Here's what the service looks like around the Strait of Gibraltar.

If you want to learn more, see the World Topographic Map information on the ArcGIS Online Resource Center.