The group-picture was taken in front of the pumping station on the location which Delfzijl is named after. In the Dark Ages there were 3 rivers that flowed together here just before flowing into the sea. By the late Dark Ages monks had put locks (in Dutch "zijl") in all three rivers, of which the Delf was the largest. Delf+zijl=Delfzijl.
The large builing on the left is pumping station "de 3 zijlen", and under it's superstructure you can see some houses in the distinctive "Amsterdamse school"-style in which most buildings in this neighborhood are built. You can also see the Protestant Cross-church behind the first houses.
Behind the left post of the Delfzijl-sign you can just make out "de Gracht", the last remaining piece of the fosse of fort Delfzijl that has survived the growth of the town since the 17th century. And on the right you can see evidence of said growth in the form of appartment buildings.
Since the late Dark Ages dykes have protected the city as it has been build on reclaimed land. Reclaimed on the sea and Delfzijl is situated meters approximately at sealevel. Without the dykes Delfzijl would only be dry at low tide...