This bicycle tunnel in Utrecht was finished in 1971 in an area of the center that was redeveloped in those days. Nowadays it is not a through route anymore and the bike tunnel is full of graffiti because this is a designated area where graffiti is legal. But it does create a social safety level that is much lower than in modern cycle facilities.
This area is to be re-developed again and the cycle tunnel will not survive this.
Bicycle tunnel
BICYCLE DUTCH 