Its railway station is a major junction and it has a port on the river Main, making it an important transport centre.

On 19 February 2020, a gunman attacked two bars and a kiosk in Hanau, murdering nine people with roots outside Germany, before shooting his mother and himself.

After a restructuring of municipal borders within Hesse in the 1970s, a couple of nearby villages and towns were incorporated.

On the 0 °C isotherm, Hanau has a humid continental climate as Eastern Germany with warm summer, classified by Köppen as Dfb.

As a result of this history, Hanau's main church stood outside its walls in the village of Kinzdorf.

In 1597 Count Philipp Ludwig II attracted French Protestant (Huguenots) refugees, who had been admitted to Frankfurt but had only very limited accommodation, to found their own settlement south of Hanau.

[4] This happened under the direction of the guardian of the Hanau count, Johann VI von Nassau-Dillenburg, who hoped for significant economic and cultural advances from the settlement of the 'Réfugiés' from south-west France.

In return for the assurance of free exercise of their religion, the refugees undertook to become economically active in Hanau.

With the arrival of the Huguenots, Walloons and Dutch, Hanau's rise to an important business location began.

[4] In 1636 it was besieged by imperial troops but was relieved on the 13 June by William V, Landgrave of Hesse-Kassel, on account of which the inhabitants commemorate that day.

Due to dynastic troubles within his family, the County of Hesse-Hanau was created a separate state from the Landgraviate until 1786.

In 1813, the Battle of Hanau took place near the city between French troops and Austro-Bavarian forces; the former won.

With its preindustrial workshops, Hanau became a nucleus of a heavy industrialisation during the 19th century from within the city (e.g., Heraeus) as well as from outside (e.g., Degussa and Dunlop).

Like all of Hesse-Kassel, Hanau was annexed to Prussia in 1866 after its prince-elector took the Austrian side in the Austro-Prussian War.

As a free-trade city, Hanau developed a silver manufacturing industry using fantasy hallmarks.

In 2010, Hanau started a huge building project to completely redesign the inner city.

[citation needed] These are the town's largest construction projects since the reconstruction after World War II.

[citation needed] On 19 February 2020, eleven people—including the perpetrator—were killed in a spree shooting at two shisha bars and a flat in the town.

[8] Starting 1 January 2026, Hanau will regain its kreisfreie Stadt (district-free city) status.