Borders - this also implies right away everything in relation to crossing borders.
What I have picked for this topic is crossing borders to a number of respects.
First of all - it's a tunnel. Its located in the centre of Hamburg in Germany. It is crossing a river and, unlike borders which usually separate, connects the city with an island in the river and overcomes the river as a border. The island as such is part of the Hamburg free harbour, free as duty free. Duty free for free trading but separated from the non-duty free city by a border, watched and protected by German customs. Duty free and isolated. The tunnel crosses this border as well (but you will have to go through customs though).
When construction was completed in 1911 it was also crossing borders in the technological sense. With its 420 meters of length and the open diameter of 6 meters for each of the two tubes, 24 meters in the ground but 12 meters of water above it, it had been quite a challenge at the time.
It is connecting - while separating to protect.
Behind the scene : how this panorama was made ▼