List of bridges documented by the Historic American Engineering Record in Pennsylvania : ウィキペディア英語版
List of bridges documented by the Historic American Engineering Record in Pennsylvania __NOTOC__ This is a list of bridges documented by the Historic American Engineering Record in the U.S. state of Pennsylvania.〔(【引用サイトリンク】Library of Congress "> Prints and Photographs Online Catalog: Historic American Buildings Survey/Historic American Engineering Record/Historic American Landscapes Survey )〕 ==Bridges==