Ciao Valentina,
we live in Amsterdam, just like another couple with 2 wolfdogs, Gerard & Monique.
There is a good camping at the outside of Amsterdam:
http://www.gaaspercamping.nl/it/index.html
As you can read, they even speak Italian!
The camping is located at the right side of Amsterdam, when it comes to walking your dogs, as it is close to forrested areas, where you are allowed to walk free with the dogs.
If you want, we could meet up and take all the dogs for a hike?
Enjoy your holidays!
Eric, Rosie & Ottokar