A sign of the (old) times


Once upon a time there was a beck, a stream, that ran through the east of the town and down to the sea. It even gave that part of town its name, Östenbäcken, The east Beck.  
As the town grew the stream got in the way and was eventually forced to run in a pipe and covered over. This hatch is one of two reminders of the stream's existence to be found in the park, next to the library where I worked for many years.
As someone who spent many youthful years exploring caves, and sometimes old mines, I've always been a bit fascinated by these hatches and find myself wondering how big the pipes are and just where the stream comes from and goes to. I wonder who has the keys to those padlocks?