The extent of the Niagara Escarpment in New York, Ontario, Michigan, and Wisconsin (marked in red).

This map's source is here archive copy at the Wayback Machine, with the uploader's modifications, and the GMT homepage archive copy at the Wayback Machine says that the tools are released under the GNU General Public License.

originally uploaded to the English Wikipedia, as en:Image:Niagara Escarpment in Red.png. history there:

(del) (cur) 17:20, 22 December 2005 . . Kelisi (Talk | contribs) . . 931×535 (29,293 bytes) (The extent of the Niagara Escarpment in New York, Ontario, Michigan, and Wisconsin (marked in red). This map's source is [http://www.aquarius.geomar.de/omc/make_map.html here], with the uploader's modifications, and the [http://gmt.soest.hawaii.edu/ GMT ) NOTE: The links to the map's source and the uploader's modifications are both dead as of December 1, 2019. Sciencebookworm (對話) 05:43, 1 December 2019 (UTC)

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