Iitti lies by the Kymijoki river in Päijänne Tavastia, in Southern Finland. Its parish village was once voted to be the most beautiful in Finland.
The municipal centre of Iitti is Kausala, by the railway and national road 12, while the Iitti parish village (Iitin kirkonkylä) lies 7.5 km to the north, surrounded by lakes.
Iitti became a parish 1539. The railroad between Riihimäki and Saint Petersburg was built in the 1960s, and Kausala became the effective centre. 1872 a paper mill was built in Kuusankoski. 1921 Kuusankoski became an independent municipality and Iitti lost most of its industry.
The section of Kymijoki between the lake Konnivesi in the north and Pyhäjärvi by the parish village has hydroelectric plants (Vuolenkoski and Mankala). These (and the former rapids) are bypassed by the Kimola canal, formerly used for timber floating, but in the 2010s upgraded for river tour boats and leisure vessels.
Trains between Helsinki and Kouvola stop at Kausala railway station 📍.
Bus station 📍.
Iitti has direct buses from Lahti, Kouvola, Kotka, Tampere and Lappeenranta.
Boating routes on Pyhäjärvi of Iitti (there are many Pyhäjärvi in Finland; max draught 1.5 m) connect Iitti parish village with Kouvola (marinas just upstream of the Kuusankoski rapids) and the Kimola canal, giving access to Konnivesi and Heinola, in turn with access to Päijänne.
Service traffic (palveluliikenne) offers dial-a-ride service.
2nd-order administrative division
Primary administrative division