Ridin' in the rain to the dunes and bunkers

Only 30 minutes from the Amsterdam Centraal station by hydrofoil ferry...

A screamin' 35 kts

...is the town of IJmuiden, which lies at the entrance to the Noordzee canal, the main shipping channel from the North Sea to Amsterdam. No, I don't know why the I and the J in IJmuiden are capitalized. There's an IJ river, and several other IJ places, too (perhaps Edwin can explain...). While I do find sea ports and monster mega-locks mildly interesting, we went there to visit the Nationaal Park Zuid-Kennemerland. This is a 10 km or so strip of sand dunes that are more or less in their original state.


Now, these are not Oregon "multiple square kilometers of moving sand dunes 150' high" (which I love visiting and going dune jumping on, as my daughter can attest). These dunes are classic depositional dunes that one finds at river mouths. They start with a long sand beach...

A long beach 

In both directions. Note the sand "hills" on the left

...and a linear sand foredune just behind the beach, which is the hill in the above photo. The foredune is held in place by grasses and tends to become fairly stable. Behind this in the swales you get freshwater (or in this case, brackish water) ponds that are linear (thought the park didn't have very many of these).  If the river has been around a long time (like, say, the Rhine), over time, the depositional process repeats, and you build plains of several rows of linear relic foredunes, and that's where the park is and the environment it supposedly protects.

On the top of a relict foredune, some 2 km inland. Ocean in the distance.

Sometimes, the wind scours the grasses off, and you get sand movement, typically parabolic in shape and in the direction of the wind. You can see the wind affected trees in the above photo, so you know it's normally windy here. But there were only two large-ish sand fields contained within the park, and neither is more than a square kilometer in size.

Scouring in the grasses 

This sand field is actually stabilizing

In motion

Also in motion, but the grasses are winning 

Classic aeolian (wind driven) patterns

There are a couple of freshwater lakes in the bigger swales.

Large lake in a larger swale from a relic foredune 3 km inland

This is an interesting national park, though not too "natural". They let cows (Highland cattle) run free in here, and they are very big and have big horns.

Big boy. Or girl. With eye level pointy bits

There are numerous farms and residences inside the park, since the park was only established in 1995. There's even an area where European bison roam free.  And it was a good place to dip my feet in the North Sea.

Cold.

So geologically, it's an interesting park, and it was an interesting place to ride to. However, 90 minutes into our ride, some 14 km from the start and almost at our turn around point, it started to rain. Fortunately, we were near a beach restaurant, so we sat on their covered porch for an hour, picnicking, staying warm (it was only 14°) and dry while it poured. (Note to Formula 1 race fans: Where we stopped was only 2 km north of Zandvoort, the site of the Dutch Grand Prix races held from 1955 to 1985).


Since we had stopped and explored most of the geology, as well as rode most of the way through the park on the way to lunch, we had some time to spare in the afternoon, so rode into IJmuiden's port area, and ran across a group of WW2 German bunkers embedded in the 2nd line of foredunes and a bunker museum (sadly not open).

Interesting rearward facing machine gun pillbox 

KC peers into a sand filled gun emplacement and tunnel access 

Trusty steeds in front of a major bunker access point 

Rows of 2 story big gun bunkers

Crawling around these was interesting, though I was not impressed that graffiti goons seem to think historic sites are good places to deface. Near as I could understand from the interpretive signs, Hitler was convinced the Allies were going to invade the continent somewhere in the Netherlands, and so had monstrous defenses and multiple rows of bunkers built to guard the port.


It was a very nice day trip, and pretty riding. The park has a ton of birds (the downside to biking is the difficulty in stopping to birdwatch). We did about 36 km on heavy 3 speed Amsterdam bikes; it would have been easier with nicer bikes, but you have to rent bikes in Amsterdam and bring them with you, and most places in Amsterdam rent pretty heavy duty bikes by the day.