{"id":"https://data.mapsnap.org/runs/v1.3/iiif/chronoscope/sanborn01790_084.keymap.iiif.json","type":"AnnotationPage","@context":["http://www.w3.org/ns/anno.jsonld"],"label":"Chicago, Illinois | 1935 | 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:g01790193502S:01790_02S_1935-0000/georef","type":"Annotation","@context":["http://iiif.io/api/extension/georef/1/context.json","http://iiif.io/api/presentation/3/context.json"],"label":"Chicago, Illinois | 1935 | sanborn01790_084 p0","metadata":[{"label":"streets","value":"98"},{"label":"intersections","value":"368"}],"created":"2026-09-21T20:11:38Z","modified":"2026-09-21T20:11:38Z","motivation":"georeferencing","target":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790193502S:01790_02S_1935-0000/selector","type":"SpecificResource","source":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790193502S:01790_02S_1935-0000","type":"ImageService3","width":1436,"height":1831},"selector":{"type":"SvgSelector","value":"<svg><polygon points=\"-0.0,1831.0 -0.0,1403.8 -0.0,-0.0 139.8,-0.0 1436.0,0.0 1436.0,1831.0 -0.0,1831.0\" /></svg>"}},"body":{"id":"https://cdn.chronoscope.io/mapsnap/service:gmd:gmd410m:g4104m:g4104cm:g01790193502S:01790_02S_1935-0000/gcps","type":"FeatureCollection","transformation":{"type":"helmert"},"features":[{"type":"Feature","properties":{"resourceCoords":[1089.7,1540.0],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6283353,41.9006001]}},{"type":"Feature","properties":{"resourceCoords":[610.1,1117.2],"type":"gcp"},"geometry":{"type":"Point","coordinates":[-87.6495766,41.9138064]}}]}}]}