Advanced growth-enhancing building of the Industrial Era. Requires Aqueduct.
The Hospital is vital for continued growth of the population in already big cities. Even with all the advancements in contemporary farming, further means are necessary to make really big cities. The Hospital comes along, directly bumping Food production in the city.
The use of a Hospital can vary based on your empire, and also when the city was built. In a wide empire, you usually settle on highly productive lands; building a Hospital allows you to work one Mine instead of a Farm for bonus Production while still slightly aiding growth (which is useful for a city whose population you intend to keep small, as it allows higher Production with fewer Citizens).
In a tall empire, the Hospital can support 5 specialists, provided you have taken the Civil Society tenet in Freedom. This allows you to replace two Farms with Trading Posts if you can already support all the specialists, which gives you more Gold than the maintenance cost of a Hospital, a small boost to growth and a small bonus to Science as well.
Finally, if you have the finances to do so, you can buy a Hospital to grow a newly settled city tall very quickly. However, if the city is coastal, an internal Food trade route can do that much more effectively. Still, if you're at your trade route limit, want super growth or expect the city to work lots of specialists, the Hospital provides a more permanent solution.
A hospital is an institution for diagnosing and treating the sick or injured, and for housing them during their recovery. Many hospitals are also teaching institutions, where student doctors and nurses learn their trade. The earliest hospitals were temples to certain gods associated with health and healing. Religious hospitals were established in Sri Lanka by 430 BC, and King Asoka of India created a chain of hospitals across Hindustan around 230 BC.