What I find special is that if I watch a Scandinavian TV serie (Danish, Swedish, Norwegian etc) I can understand a lot of words, that are the same or similar to us - that's interesting. I once did voluntary work with a Dutch girl (originally from Surinam) and she said similar. She could understand Swedish.
(She spoke English, Dutch, German & Spanish.)
German we understand because Dutch is a "low German" language - yes, I've read a little about this. Dutch and Deutsch share similar origins.
In the US, 'Pennsylvanian Dutch' is actually a German dialect.
In addition to Nederlands, the language of The Netherlands and Flanders, isn't there also a dialect called Low Saxon, spoken in parts of Germany and The Netherlands?
I know there is a Low German variety in Northern Germany (Niederdeutsch/Nedderduutsch).
English is very similar to the Frisian language, the language of our region Friesland - yeah, I've read a little about this, too. This is West Frisian (there are also Saterland Frisian and North Frisian).
Most Dutch speak and understand English because we have many English TV series and subtitled to Dutch - which aspects, if any, of English do Dutch people find difficult?
I find it easier to make some sense of written Dutch as opposed to the spoken language, on account of the similarities with German (e.g. quite a bit of shared or similar vocabulary, similar/same word order).
Dutch pronunciation, especially vowels - deary me! XD