The Netherlands introduced new entry requirements in early September that required visitors that had been in select high-risk countries, including the US, to quarantine upon arrival regardless of their vaccination status.
The country is relaxing coronavirus-related restrictions from September 25 for those that can prove that they have been vaccinated and allow fully inoculated visitors from countries designed as high risk, such as the US and UK, to enter without quarantine from September 22.
You can access the Netherlands page for Covid-19 related restrictions here.
Here’s an excerpt from that page:
The rules on self-quarantining for people travelling to the Netherlands will change as of 22 September. Vaccinated travellers from the United States, the United Kingdom and other very high-risk areas no longer have to self-quarantine on arrival in the Netherlands. Prepare your journey well. Before you leave, check the travel advice on wijsopreis.nl (in Dutch) and reizentijdenscorona.rijksoverheid.nl/en.
Hilton hotel experiences in the Netherlands this August:
There are still some restrictions in place in the Netherlands past September 25, 2021; bars and clubs must close at midnight and allow up to 75% of the maximum number of people to enter. In addition, a face mask must be kept on in public transit and airport.
I spent two weeks in the country last month, and it was mostly business as usual.