| 1930s_airphotos_88 | 1930's Digital Orthorectified Image of Union County, Iowa, in MrSid Format | |
| 1950s_airphotos_88 | 1950's Digital Orthorectified Image of Union County, Iowa, in MrSid Format | |
| 1960s_airphotos_88 | 1960's Digital Orthorectified Image of Union County, Iowa, in MrSid Format | |
| 1970s_airphotos_88 | 1970's Digital Orthorectified Image of Union County Iowa | |
| 1980s_CIR_airphotos_88 | 1980's Digital Orthorectified Image of Union County, Iowa, in MrSid Format | |
| 1990s_airphotos_88 | 1990's Airphoto Mosaic for Union County | |
| 2002_CIR_88 | 2002 Color-Infra-Red Airphoto Mosaic for Union County | |
| 2004_NAIP_airphotos_88 | 2004 National Agriculture Imagery Program (NAIP) Aerial Photography for Union County, Iowa | |
| 2005_NAIP_airphotos_88 | 2005 National Agriculture Imagery Program (NAIP) Aerial Photography for Union County, Iowa | |
| 2006_NAIP_airphotos_88 | 2006 National Agriculture Imagery Program (NAIP) Aerial Photography of Union County, Iowa | |
| 2007_NAIP_airphotos_88 | 2007 National Agriculture Imagery Program (NAIP) Aerial Photography of Union County, Iowa | |
| 2008_NAIP_airphotos_88 | 2008 National Agriculture Imagery Program (NAIP) Aerial Photography Mosaic of Union County, Iowa | |
| 2009_CIR_airphotos_88 | 2009 Two Foot Pixel, Color Infrared Orthophotography Mosaic of Union County Iowa | |
| 2009_color_airphotos_88 | 2009 Two Foot Pixel, Color Orthophotography Mosaic of Union County Iowa | |
| 2009_NAIP_airphotos_88 | 2009 National Agriculture Imagery Program (NAIP) Aerial Photography Mosaic of Union County, Iowa | |
| 2010_NAIP_airphotos_88 | 2010 National Agriculture Imagery Program (NAIP) Aerial Photography Mosaic of Union County, Iowa | |
| 2011_NAIP_airphotos_88 | 2011 National Agriculture Imagery Program (NAIP) Four-Band Aerial Photography of Union County Iowa | |
| andreas_atlas_88 | Georectified Image of Union County from the Illustrated Historical Atlas of the State of Iowa, 1875, by A.T. Andreas | |
| census_1990_88 | US Bureau of the Census, 1990 STF3a block level for Union County, Iowa | |
| census_2000_blocks_88 | Union County Census 2000 Blocks | |
| common_land_unit_88 | Common Land Unit for Union County, Iowa | |
| contours_2ft_88 | Generalized Two Foot Contours of Union County Iowa Derived from Lidar Data | |
| DEM_3M_I_88 | Three Meter Digital Elevation Model of Union County Iowa as an Imagine 16-bit Integer Raster | |
| DOT_roadmap_88 | Iowa DOT Union County Highway Transportation Map, 2005 | |
| GLO_maps_88 | General Land Office (GLO) Maps of the State of Iowa, as Surveyed from 1836-59, Union County | |
| GLO_vegetation_88 | Government Land Office Vegetation 1832-1859 for Union County, Iowa | |
| Hillshade_1M_88 | Hillshade of Union County Iowa Derived from the LiDAR One Meter Digital Elevation Model | |
| HRLC_2009_88 | High Resolution Landcover of Union County Iowa, 2009 | |
| NWI_88_line | National Wetlands Inventory data for Union County, Iowa | |
| NWI_88_poly | National Wetlands Inventory data for Union County, Iowa | |
| NWI_remap_line_88 | National Wetland Inventory Remap and Update, Line Features, of UnionCounty, Iowa | |
| NWI_remap_poly_88 | National Wetland Inventory Remap and Update, Polygon Features, of UnionCounty, Iowa | |
| PLSS_88 | Public Land Survey System for Union County, Iowa | |
| PLSS_QQQ_88 | Public Land Survey System, Quarter-Quarter-Quarter Sections, of Union County Iowa | |
| rivers_88 | Rivers of Union County | |
| roads_2006_88 | Road Centerlines of Union County, Iowa, 2006, from Iowa DOT GIMS files | |
| soils_88 | Iowa Cooperative Soil Survey (ICSS) Digital Soil Data for Union County | |
| spot_88 | Digital spot data for Union County, Iowa | |
| ssurgo_line_88 | Soil Survey Geographic (SSURGO) database for Union County, Iowa | |
| ssurgo_soil_88 | Soil Survey Geographic (SSURGO) database with attached Iowa Soil Properties And Interpretations Database (ISPAID) for Union County, Iowa | |
| ssurgo_spot_88 | Soil Survey Geographic (SSURGO) database for Union County, Iowa | |
| USGS_quads_88 | USGS 7.5' Quad Mosaic for Union County |