{"id":"https://data.mapsnap.org/runs/v1.3/iiif/chronoscope/sanborn01790_008.keymap.iiif.json","type":"AnnotationPage","@context":["http://www.w3.org/ns/anno.jsonld"],"label":"Chicago, Illinois | 1896 | key map | mapsnap generated fit (2026-09-21)","creator":{"type":"Software","name":"mapsnap","homepage":"https://mapsnap.org"},"rights":"https://opendatacommons.org/licenses/odbl/1-0/","metadata":[{"label":"generated","value":"2026-09-21"},{"label":"run","value":"corpus-v1"}],"items":[{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g017901896B:01790_B_1896-0000/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1896 | sanborn01790_008 p0","metadata":[{"label":"streets","value":"106"},{"label":"intersections","value":"906"}],"created":"2026-09-21T14:18:06Z","modified":"2026-09-21T14:18:06Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g017901896B:01790_B_1896-0000/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g017901896B:01790_B_1896-0000","type":"ImageService3","width":1422,"height":2126},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"0.0,2126.0 0.0,-0.0 1422.0,-0.0 1422.0,2126.0 0.0,2126.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g017901896B:01790_B_1896-0000/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[937.0,1784.5],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7230858,41.8350906]}},{"type":"Feature","properties":{"resourceCoords":[1036.5,821.8],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.7163766,41.8972946]}}]}}]}