Conservation and restoration 277 Historic buildings 72 History 49 Architecture 46 Historic sites 40 Books 32 Photographs 24 more ... Paper 21 Preservation 21 Conservation of natural resources 20 Manuscripts 19 Periodicals 18 Buildings, structures, etc 16 Library materials 15 Architecture, Domestic 14 Art objects 14 Historic preservation 14 Archives 12 Conservation et restauration 12 Museum conservation methods 10 Art 9 Conservation 9 Conservative Judaism 9 Handbooks, manuals, etc 9 Libraries 9 Monuments 9 Nature conservation 9 History, Local 8 Protection 8 Antiquities 7 Archival materials 7 Bibliography 7 Buildings 7 Canning and preserving 7 Collection and preservation 7 Conservation et mise en conserves 7 Cultural property 7 Historic houses, etc 7 Jews 7 Painting 6 less ...