History 15,233 Maps 7,350 Buildings, structures, etc 6,465 Buildings 6,225 Law and legislation 4,741 Roads 4,489 Real property 4,461 City planning 3,745 Education 3,726 Theses 3,139 Politics and government 2,881 Floods 2,857 Regional planning 2,654 Finance 2,580 Planning 2,528 Groundwater 2,379 Insurance, Flood 2,318 Fire insurance 2,264 Fire risk assessment 2,231 SIUC 2,212 Geology 2,124 Registers of births, etc 2,071 Study and teaching 2,028 Environmental aspects 1,912 Pollution 1,901 Periodicals 1,869 Universities and colleges 1,855 Statistics 1,739 Illinois State University 1,663 Housing 1,588 African Americans 1,587 Agriculture 1,574 Maps, Topographic 1,570 Landowners 1,518 Railroads 1,455 Land use 1,437 Services for 1,429 Wells 1,424 Curricula 1,423 Economic conditions 1,401 Dissertations 1,398 Historic buildings 1,365 Vocational education 1,362 Social conditions 1,360 Census districts 1,346 Quality 1,331 Description and travel 1,312 Transportation 1,308 Teachers 1,307 Architecture 1,270 Parks 1,268 Community development 1,222 Taxation 1,184 Streets 1,172 School districts 1,169 Library buildings 1,168 Coal mines and mining 1,154 Economic aspects 1,135 Directories 1,134 Evaluation 1,125 UIUC 1,106 Students 1,098 Population 1,097 College buildings 1,091 Water 1,091 Cemeteries 1,076 Biography 1,070 Antiquities 1,068 Attitudes 1,067 Social life and customs 1,027 Vocational guidance 1,019 School buildings 1,011 Research 986 Women 986 Water-supply 973 Design and construction 956 Flood insurance 925 Indians of North America 925 Zoning 925 Management 902 Traffic flow 902 Employees 899 Administrative and political divisions 863 Officials and employees 863 Soils 860 Prevention 854 Historic sites 853 Church history 849 Public schools 846 Law 834 Genealogy 827 Training of 816 Employment 814 Societies, etc 801 Older people 792 Schools 782 Education, Higher 777 Church buildings 773 Accounting 768 Local transit 767