I'm researching rail infrastructure costs. Can you find the construction cost per kilometer for the Barcelona rail tunnel mentioned on this website? Please provide the cost.
Navigate to 'pedestrianobservations.com' Click on the 'Construction Costs' link in the navigation menu. On the 'Construction Costs' page, locate and click the 'Quick Note: Barcelona Rail Tunnel' link. Extract the construction cost per kilometer for the Barcelona rail tunnel from the article. State the extracted construction cost.
Successfully navigate to the 'Construction Costs' page. Successfully navigate to the 'Quick Note: Barcelona Rail Tunnel' article. State the construction cost per kilometer for the Barcelona rail tunnel as approximately $40 million.