I am trying to create a story map, however the space that I want to use doesn't have any details in aerial views - just grey area. Is there a way for me to upload a drawn map of the area to use as a base?
You might like using Custom Basemap in ArcGIS Online. Make sure the image is georeferenced.
If you want to create tiled service, also check Publish a Tiled Service to ArcGIS Online w/o ArcGIS for Server or Utilizing Your Credits
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