Is that where it is best used?

90M€ of tax payers' money used for a 500m tunnel … why? To get few new block of flats and a bit more peace for those few hundred living next to current road?
Temped to say that the only/main reason is lobbing from construction companies.
Well whatever… not the wisest way of using 90M€ when state/cities are saving in education, health care, … everything.