Neoclassism was introduced into the city in the 1840s, at the time including Gas public lighting in 1848 and the railroad in 1837. In the second half of the 18th century, sugar and coffee production increased rapidly, which became essential in the development of Havana's most prominent architectural style. Many wealthy ''Habaneros'' took their inspiration from the French; this can be seen within the interiors of upper-class houses such as the ''Aldama Palace'' built in 1844. This is considered the most important neoclassical residential building in Cuba and typifies the design of many houses of this period with portales of neoclassical columns facing open spaces or courtyards.