Built in 1837, the Eteläkylän Isosilta bridge in Pyhäjoki is the oldest wooden strut-frame bridge still in use in Finland and a national road museum site.
The four-arch double-strut bridge stands on wedged stone supports and is 77.5 metres long and 5.8 metres wide. The bridge has been maintained and repaired multiple times but, according to a study conducted in 1987, the load-bearing structures of the bridge still held some of the original timber. The local Centre for Economic Development, Transport and the Environment initiated a full renovation of the bridge in 2018. The renovations will be conducted with due consideration to the old structural models and work methods, and the Finnish Heritage Agency has provided instructions for the work. In fact, a pleasant smell of tar wafts in the area surrounding the bridge.
Since the deck of the bridge is made of wood, it has been slippery when wet. It is said that a lorry carrying people on their way to a dance once veered off the bridge as a result. Apparently no one was hurt, however, as everyone managed to hop off the lorry bed in time. According to another story, some prison escapees burst through railing during a chase.