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 # NSHM: Conterminous U.S.
 
 National Seismic Hazard Model (NSHM) for the conterminous U.S. This model is intended for use with
-U.S. Geological Survey (USGS) hazard software [*nshmp-haz*][1]. This model was last updated in
-2018.
+U.S. Geological Survey (USGS) hazard software [*nshmp-haz*][1].
 
 For details on the format of this model, see the *nshmp-haz*
 [user guide and implementation reference][2].
 
+## Site Files
+
+The `map-conus.geojson` file defines the latitude-longitude range over which the USGS computes
+maps of seismic hazard from this model. The `sites-conus.geojson` and `sites-conus.csv` files
+contain the test sites at which the USGS performs more detailed comparisons between model editions.
+See the *nshmp-haz* user guide [site specification section][3] for more details on these files.
+
 ## Reference
 
 Petersen, M.D, Shumway, A.M., Powers, P.M., Mueller, C.S., Moschetti, M.P., Frankel, A.D.,
 Rezaeian, S., McNamara, D.E., Luco, N., Boyd, O.S., Rukstales, K.S., Jaiswal, K.S., Thompson, E.M.,
 Hoover, S.M., Clayton, B.S., Field, E.H., and Zeng, Y., 2020, The 2018 update of the U.S. National
-Seismic Hazard Model: Overview of model and implications, _Earthquake Spectra_, 36(1) p. 5–41.
+Seismic Hazard Model: Overview of model and implications, _Earthquake Spectra_, 36(1) p. 5–41,
+DOI: [10.1177/8755293019878199][4].
 
 [1]: https://code.usgs.gov/ghsc/nshmp/nshmp-haz
 [2]: https://code.usgs.gov/ghsc/nshmp/nshmp-haz/-/blob/main/docs/README.md
+[3]: https://code.usgs.gov/ghsc/nshmp/nshmp-haz/-/blob/main/docs/pages/Site-Specification.md
+[4]: https://doi.org/10.1177/8755293019878199