From the Bridges board/category. [Bridge in Parque Nacional Fragas del Eume, Galicia, Spain (by RTH FOTOS). [Bridges have lots of "lines." Also, this bridge reminds me of train tracks that have lots of lines.
This beautiful Arc de Triomf was built for the 1888 Barcelona Universal Exposition, which took place at the Parc de la Ciutadella. The Arc de Triomf, situated at the end of a wide promenade, served as the exposition's main entrance.