Important new information added!
You will need a bit of planning to arrange your trip to the Island of Terschelling since you are subject to train and ferry timetables. Here we aim to provide you with enough information to make all the necessary arrangements with links to hotels in the (not so remote) event of not being able to arrive on the same day in the Netherlands and on Terschelling.
It is easy and relatively cheap to travel in the Netherlands by train. The Schiphol (Amsterdam airport) train station is located directly under the arrivals hall. You need to buy a train ticket to Harlingen Haven (Harlingen Harbour), which is the station at the port where you catch the Ferry to the Island of Terschelling. There are regular trains from Schiphol which get you to Harlingen Haven every 30 minutes. You first need to get an intercity train going in the direction Amersfoort/Groningen/Leeuwarden/Enschede which typically leaves Schiphol at 21 and 51 minutes past the hour, but you can check the website http://www.ns.nl for details. This site also provides a railway map in PDF format. The whole journey takes around 3 - 3:30 hours and you typically need to change trains twice. First in Amersfoort and the second in Leeuwarden. It takes about 40mins to get to Amersfoort from Schiphol, and you have to change trains to catch the intercity to Leeuwarden. You may only have to get on to a different part of the same train on the same platform. Make sure to get the right part of the train: you need the back of the train going to Leeuwarden, the front goes to Groningen which is not the most direct route to Harlingen. Don't hestitate to ask people around to be sure. Almost everyone in the Netherlands can speak English. Amersfoort to Leeuwarden takes 2 hours, then you have to take a local train to Harlingen.
The cost of the trip by train is around 27 euros each way. A return
costs twice a single, and if you wish to buy a return ticket in
Schiphol make sure you are clear on which day you wish to return. The
default is a day return.
The last train from Schiphol that enables you to reach
Harlingen departs around 20:51 from Schiphol and
arrives in Harlingen at around 23:45. However, with this train
you have missed the last ferry.
You can check the English website of the Netherlands Railways for
information: http://www.ns.nl.
The Dutch railways are going to be doing work on the railway lines between Amsterdam and Amersfoort on 1st, 2nd & 3rd July. This means that there will be delays in your train journey to Leeuwarden. The most important thing to note is that you will have to travel first from Schiphol to Amsterdam central station.
From there you will have to catch a train to Leeuwarden (sometimes changing trains in Amersfoort). This means that your train journey may take about 30 minutes longer than it should from Schiphol. There is a train every 30mins from Amsterdam CS to Leeuwarden.
For your information, to help your planning: From Leeuwarden you need to catch a regional train to Harlingen Haven.
There are 6 ferry sailings on Sunday 3rd July to Terschelling from Harlingen Haven (3 fast, taking 45mins and 3 slow taking 2 hours - fast ferries cost more).
To help in your planning, I list here the times of the ferry departures, and the time of the train you can get from Schiphol Amsterdam CS and Groningen to be able to get this ferry, assuming all the connecting trains are caught. You will need some time at the end of your train journey to buy the ferry ticket.
Ferry departure times from Harlingen Haven:9.45 am 12.30 pm (fast) 15.00 17.30 (fast) 19.30 (fast) 19.45
Here I give an indication of the train times to get these ferries. We recommend you take plenty of time to spare - these are the last possible connections you can make.
To catch these ferries, you need to leave Schiphol at least by this time (on the train to Amsterdam CS)
07.18 to get 9.45 ferry 08.31 12.30 11.01 15.00 13.31 17.30 15.31 19.30 16.01 19.45Leave Amsterdam CS on or before:
08.06 to get 9.45 ferry 09.06 12.30 11.36 15.00 14.06 17.30 16.06 19.30 16.36 19.45Leave Groningen CS on or before:
10.20 to get 12.30 ferry 12.20 15.00 15.20 17.30 17.20 19.30 17.20 19.45
Another, more expensive, possibility to travel to Harlingen Haven is using the Schiphol taxi service. This service needs to be booked at least 24 hours in advance. You can check it at http://www.schiphol.nl/. (The Harlingen postcode is 8861, you will need to enter this to calculate the price and make the reservations). The approximate cost is 146 euros for a private taxi and 46 euros per person for a shared taxi. In the case of a shared taxi, other passengers may be collected along the (not necessarily direct) way.
If you cannot make it from Schiphol to Harlingen the day you arrive you could look for a hotel either around Schiphol or continue on your way and spend the night either in Leeuwarden, Groningen or in a Friesian town, such as Sneek or even at Harlingen. To check for accommodation at any of these places you can go to http://www.holland.com/global/ Click on 'look&book 'and then 'accommodation' and you will find any kind of lodging at any place you wish in the Netherlands. On the same link there is all sorts of general information about the country.
You do not need a car to travel around the Netherlands and although you could take it into the island you have to make reservations well in advance (http://www.rederij-doeksen.nl/engels/NEDINDEX7.htm). There is also a long term car park in Harlingen, but it is quite a long walk from the ferry, so allow plenty of time for this. If you want to rent a car, then Schiphol Airport is equipped with a full array of rental car companies. Road traffic rules in the Netherlands hardly differ from those in other Western countries. The one rule to remember is to give way to traffic coming from/turning to the right, because unlike for instance in the US or UK, not all intersections have "STOP" or "Give Way" signs.
Once you are in Harlingen Haven you will need to get a Ferry into the Island.
The last ferry departs Harlingen at 19:45 but it does not do so daily, so
for a detailed timetable check:
http://www.rederij-doeksen.nl/pdf/3360-002_Dien%8Aregeling_enge.pdf
The return ticket is around 20 euros, depending if you take the
fast or the slow boat.
And finally, once you are in the Island a nice and ecological way to get around is to rent a bike. There are plenty of choices (you can again check http://www.holland.com/global/ and search for bike rental) at Terschelling with a price around 4.5 euros per day. You can of course bring your own bike.