I'm trying to plot some GPS coordinates onto the World Light Gray Canvas basemap, but they are not showing up near the correct location (Ecuador). I uploaded a shapefile for Ecuador which did show up in the correct location on the basemap, so I'm not sure why the lat/long are so far off.

Spatially, the locations appear to be the correct distance from one another, but they are showing up near the prime meridian instead of off the coast of South America.

I have the coordinates in decimal degrees in an excel file (0.32, -89.95), and I'm adding the XY data with X=long, and Y=lat, and the coordinates should be WGS_1984 (I got them from google maps, so probably the mercator projection?)

Steps I took: Add data--> Add excel sheet with coordinates --> Display XY Data--> X Field=Long, Y Field=Lat, Coordinate System=GCS_WGS_1984

Any ideas???

  • 3
    Sounds like a projection issue. What projection are your GPS data in?
    – lambertj
    Commented Jan 9, 2019 at 16:28
  • Adding on to @lambertj, what projection is the project in? Commented Jan 9, 2019 at 16:40
  • I put it in a table and used "Add XY" in ArcMap using GSC_WGS_1984 as the coordinate system and it put it right by the Galapogos Islands. I entered it in without specifying a coordinate system and it placed it just off the coast of Nigeria, near the prime meridian.
    – Pete
    Commented Jan 9, 2019 at 17:00
  • The data is just standard GPS coordinates (WGS_1984), and I've been specifying that as the coordinate system, but still nothing. Is "AddXY" different than uploading an excel sheet? The way I'm doing it makes me specify a coordinate system
    – Anna Zarn
    Commented Jan 9, 2019 at 17:17
  • 1
    Before you add or create the event layer change the data frame CRS to WGS 1984 and then create/add the event layer. See if that plots the points in the correct location.
    – artwork21
    Commented Jan 9, 2019 at 18:14

1 Answer 1


As I noted in my comment, to get the points to align correctly on the map change the data frame CRS to match the coordinates in the excel (to WGS_1984) OR in the event load dialog define the event layer CRS to WGS_1984 (use the Edit button). The app. was plotting GCS points on a PCS map without knowing the source CRS (or being defined incorrectly as a PCS) of the event layer.

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