One of the things that shocked me the most about coming to Europe was the lack of free water. At a restaurant, a small bottle, less volume than a free glass at any American restaurant, will cost upwards of three or four euro. But upon further examination, there are ways to access clean, safe, and free drinking water.
In some larger cities, like Rotterdam for example, there are free drinking taps around. It is just a matter of spotting them, a silver box that can blend in with city-wide utility system boxes. Labeled 'drinkwater', these free taps supply chilled and clean water right on the sidewalk.
Additionally, there are other water taps around that are part of an organization called Join The Pipe. By using the sales of water bottle distribution, they install tap water fountains around urban and rural areas. Their goal is to create a fair water distribution system because they believe that everyone has a right to drink water. I first learned about this while volunteering at the rooftop art installation, as these were the water bottles provided for us as well as a tap station on sight. Our hostel in Amsterdam also has a tap inside which is very convenient. Join The Pipe is the first tap water company to be distributed globally around all major cities.
While I've seen more Join The Pipe taps around and more advertising for them, tap water from various distribution systems can be found for free around the Netherlands. This is something I have definitely taken advantage of once discovered them instead of having to pay for water in a glass bottle from a restaurant.