Dear Captain Kernow,
It seems most of the people advising you are still living in the 1980s.... The good places for shipspotting in Rotterdam are no longer Maasluis or Rozenburg or Vlaardingen, not even the 'land tong' !! Shipping has changed completely in Rotterdam over the last 15-20 years and most of the traffic has moved to Europoort and the Maasvlakte, with only smaller tonnage passing Maasluis (feeders, chemical carriers, very few large containerships, the odd reefer - if you are lucky). A day at Maasluis/Rozenburg could actually prove very boring unless you are a big fan of small ships !
If you really want to see exciting shipping movements (large containerships, bulkers, tankers) and virtually spot EVERY ship coming in and going out of the port, you need to go to the very port entrance at the MAASVLAKTE. Obviously it is a long way to go from Rotterdam city, and you need a car for that, but the advantage for your father is that you can park your car on the beach over there, and spot ships from your car, without having to walk. The place is truly spectacular, you wont be disappointed. You may find Hotels/pensions at the nearby city of Oostvorne - not so close any more since the construction of MASSVLAKTE 2 but still easy to reach daily by car from the spoting place at the MAASVLAKTE/port entrance.
A good - but expensive- hotel at Oostvorne is Wapen Van Marion. You may google the name to get more info.
Hope the above helps
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