05-11-2023-0753 - The village of Hallstatt in Austria, which is known for its long history of salt mining, claims to contain "the oldest industrial pipeline in the world", dating back to 1595.[34] It was constructed from 13,000 hollowed-out tree trunks to transport brine 40 kilometres (25 mi) from Hallstatt to Ebensee.[35]

Brine

The village of Hallstatt in Austria, which is known for its long history of salt mining, claims to contain "the oldest industrial pipeline in the world", dating back to 1595.^[34] It was constructed from 13,000 hollowed-out tree trunks to transport brine 40 kilometres (25 mi) from Hallstatt to Ebensee.^[35] 

https://en.wikipedia.org/wiki/Pipeline_transport#Oil_and_natural_gas