That is the well-known Frankenstein trestle. It is named by the way after the listed 19th century artist Godfrey Frankenstein who was trained in the Dusseldorf School tradition and who immigrated to the US in the early 19th century. At this time, the White mountains attracted many of the early romantic artists coalescing the romantic luminescent School of painting expanding uponthe Dusseldorf landscape style in which they had been trained... Crawford notch was a popular place to paint. The fantastic colors and the rugged natural scenery, and of course the relative accessibility from Boston or New York garnered much enthusiasm. This particular phase is called the White mountain School and had many famous participants from Thomas Cole to Albert Bierstadt. It is related to well known Hudson River School and was influential and establishing American landscape studio and plein aire painting. Many of the best known of the 19th century artist started here, before the opening of the Great West and accessibility