Additional Information

Contact Information

The Finnish Transport Infrastructure Agency

Project Manager

Janne Wikström

  • 029 534 3600

The Finnish Transport Infrastructure Agency

Project Manager

Juha-Pekka Hämäläinen

  • 029 534 3563

Lahti Southern Ring Road

Road project Ongoing

The aim of the project is to ensure smoother and safer transport along the busy main road No 12 and to improve conditions for land use development and business throughout the Lahti region.

  • Planning
  • Year 2017 - building of part 2 begins
  • Year 2018 - building of part 1A and 1B begins
  • Completion

Basic information of the project

Destia, VALTARI-alliance, Suomen Maastorakentajat
275 000 000 €
Responsible parties
Finnish Transport Infrastructure Agency
  • Considerable improvement of traffic safety and flow
  • New opportunities for the economic life and from the perspective of land use
  • Comfort of living improves and the risk of groundwater contamination reduces

Lahti Southern Ring Road

Background to the project


The Lahti Southern Ring Road project involves rerouting main road No 12 to the south of Lahti and improving regional road No 167, which enters Lahti from the south.

Main road No 12 is a major national east–west route. The road currently runs through the centre of Lahti and built-up areas of Hollola.

The project consists of two works sites and three separate contracts.

Subproject 1A involves widening the Lahti Southern Ring Road at the Hollola end to provide two lanes along main road No 12 between Soramäki and Okeroinen as well as building 17 bridges.

Subproject 1B covers the southern end of the Lahti Southern Ring Road. The works site begins to the east of the Okeroinen interchange and ends at the Joutjärvi interchange. This is a technically challenging stretch of the road, and the project involves, among other works, building several interchanges as well as two tunnels. Read more about the plan from the Project plan for the development phase and Value for Money report published on May 29th, 2018.

Subproject 2 involves widening Uudenmaankatu to provide four lanes along regional road No 167, which enters Lahti from the south, between Renkomäki and Laune. The project also involves renovating underpasses and bridges.

Works along regional road No 167 began in the spring of 2017 and works along main road No 12 in the spring of 2018. The goal is to reopen main road No 12 to traffic towards the end of 2020. Finishing works will take place in 2021, and final surfacing is scheduled for 2023.

Objectives of the project

Rerouting main road No 12 further south will improve traffic safety and flow considerably, as it will divert traffic away from the centres of Lahti and Hollola. Comfort of living will improve in residential areas once traffic is diverted elsewhere, and lower traffic volumes will mean lower noise levels, emission levels and congestion in the surroundings of the current route of main road No 12. Safer and smoother traffic will also improve the reliability of goods transport.

From the perspective of land use development, the Lahti Southern Ring Road will provide new opportunities for developing the area around Lahti railway station, the former plot of the Asko furniture factory, the Sopenkorpi district and the centre of Hollola.

The bypass will promote the development of the Nostava logistics park and create efficient transport links to the Kujala and Lotila industrial parks.

Rerouting main road No 12 further south will also reduce the risk of groundwater contamination in the Salpausselkä area, which is an extremely important source of groundwater.

Cost of the project

The project is estimated to cost a total of EUR 275 million. The investment in the Lahti Southern Ring Road is estimated to amount to EUR 258 million and the investment in regional road No 167 to EUR 17 million. The Finnish State is paying 72% of the costs (EUR 198 million), and the remaining 28% (EUR 77 million) is split between the local authorities of Lahti and Hollola.