Not specific to Birmingham but still relevant. A 3 min commentary on wartime features along our canals. On your next stroll along a canal look out for pill boxes, stop devices and anti-tank defences. Viv.
https://canalrivertrust.org.uk/enjoy-the-waterways/canal-history/war-on-the-waterways?
https://canalrivertrust.org.uk/enjoy-the-waterways/canal-history/war-on-the-waterways?