LC ClassificationTC

19th century(24) activism(6) Africa(11) agriculture(26) American(12) American West(25) archaeology(10) architecture(56) Arkansas(5) beach(5) biography(28) boats(30) bridges(5) California(72) Canada(8) canals(124) cartography(5) civil(12) climate(11) climate change(24) conservation(25) construction(38) development(15) disasters(7) ecology(38) economic history(5) economics(17) Egypt(23) energy(15) engineering(165) environment(119) environmental(13) environmental issues(5) environmental policy(5) environmental studies(6) environmentalism(7) Europe(11) factual(8) geography(44) geology(30) Germany(30) global warming(9) Great Depression(12) green(10) handbook(7) history(464) imperialism(5) industry(7) lighthouses(22) management(8) maps(7) maritime(8) Middle East(10) natural disasters(7) natural resources(9) nature(29) nautical(6) New Deal(14) New Jersey(5) New Mexico(37) New York(20) Northwest(5) ocean(9) oceanography(5) photographs(17) photography(41) pink(9) policy(8) politics(38) reference(30) resources(8) rivers(60) science(80) Scotland(9) sea(8) shipping(8) ships(26) Southwest(14) sustainability(11) topography(10) travel(40) U.S. History(8) usa(41) Washington(12) watershed(13) windmills(5) World's Fair(10)