longitudinals
"The historic Salt Mine in Wieliczka is the only mining site in the world functioning continuously since the Middle Ages. Its original excavations (longitudinals, traverses, chambers, lakes, as well as minor and major shafts) are located on nine levels and extend for the total of about 300 kilometres: reaching the depth of 327 metres they illustrate all the stages of mining technology development over time."
Andretravel 17/07/2011 21:00
Nikkor AF-S DX 35 mmf/1,8G