The city is broken up into three tiers that span a large hill. The port and lower city are located in the lowest tier, followed next by the business district called Hadar HaCarmel (or simply Hadar), then the highest one, the Carmel district, a mostly residential area known for its panoramic views. Haifa's modern-day development came as a result of transportation and immigration. In 1905, the Haifa-Damascus Railway was built, followed by a railway link with Egypt in 1919. The biggest boon to Haifa's development came when the British began building a modern port in 1929.