Al Shindagha tunnel is in Dubai.
The tunnel goes under the Dubai Creek to connect the neighbouring places of Al Ras and Deira and Al Shindagha.
It is operational since 1975 – for the last 43 years it has been used as a means to cross the Dubai Creek which is a salt water body from the Persian Gulf. The tunnel clearance is 5 meters. So you will not find big trucks or huge vehicles using this tunnel.
There are 2 lanes in each direction – total 4 lanes. And the maximum speed to drive through the tunnel is 60 km/h – so no speeding in this tunnel. Still, it is the busiest tunnel in Dubai with around 55,000 vehicles crossing both ways daily.
There is Al Shindagha pedestrian tunnel parallel to this vehicle tunnel which I have yet to find out.