Railroads 557 History 127 Street-railroads 106 Finance 88 Canals 60 Description and travel 34 Streets 33 more ... Transportation 33 Railroad stations 31 Underground Railroad 29 Early works to 1850 27 Design and construction 23 Railroad law 23 Railroad mortgages 20 Local transit 19 African Americans 18 Electric railroads 18 Coal mines and mining 17 Rates 17 Coal 15 Surveying 15 Taxation 14 Antislavery movements 13 Fugitive slaves 13 Railroads, Elevated 13 Freight 12 Law and legislation 12 Right of way 12 Street railroads 12 Commerce 11 Bridges 10 Costs 10 Management 10 Appropriations and expenditures 9 Bus lines 9 Church buildings 9 Coal trade 9 Railroads and state 9 Location 8 Mergers 8 less ...