With a recent ArcGIS Online update the USA Topo basemap (containing the USGS topo map services) no longer appears in the ArcGIS.com map viewer and Explorer Online basemap galleries. The basemap was replaced by others having more global coverage.
Though it no longer appears in the gallery, the USGS topographic maps continue to be available and can be easily found and used as your basemap whenever you want. Here’s an easy way how to find and use them as your basemap:
Open the ArcGIS.com map viewer with a new map and click Add, then choose Search for Layers:
Search for “USA Topo” and it will appear at the top of the search list:
Click on the title to display additional options, and choose Use as Basemap:
Start Explorer Online and click the New Map arrow, then choose Advanced…
Click Search, then enter “USA Topo”
Finally, click Create Map to open a new map using the USA Topographic map as your basemap.
Save the maps you’ve created above and you’ll have them handy whenever you want to start with the USGS topos as your basemap.
For more information see the following help topics: