Inspired by the aesthetics of Gustave Eiffel, Alberto de Palacio transformed a small railway station into a grand building in the middle of the 19th century. To this end, he combined the use of wrought iron, which was in vogue at the time, with brick, a material prevalent in the walls of Madrid. Taking cues from the latest advances in engineering he, thus, created an eclectic structure with a central nave that housed up to 6 railway lines, being far wider than the majority of European stations at the time. By 1985, more space was needed and architect Rafael Moneo was placed in charge of the expansion of the original station. The central nave was taken out of service and was converted into a tropical greenhouse with about 7,200 plants of 260 different species - even palm trees - creating here a welcoming summer oasis all year round!