Take the A-1 motorway towards Amersfoort. Leave the motorway at the Naarden West exit. On the slip road, take the first left and then immediately turn left again. You now continue on the service road alongside the A-1 (no entry does not apply) as far as the 'Witte Toren'. The entrance is in the ‘Witte Toren’, on the first floor.
Take the A-1 motorway towards Amsterdam. Leave the motorway at the Naarden/Bussum exit and follow signs for Naarden. You then come to a traffic light junction and can see NH Hotel Jan Tabak diagonally opposite. Go straight ahead at these traffic lights. At the roundabout, take the second exit (straight ahead). After passing another traffic light junction, you come to a busy traffic light junction with a block of flats on the left. Here again go straight ahead. After approximately 900 metres watch out for a small sign saying 'De Witte Toren' (on the right of the road). Turn right here and then immediately turn left onto the parallel road. This is Rijksweg. You go under the motorway and arrive at the Witte Toren. You will find Value Proof at no 81b. The entrance is under the Witte Toren, on the first floor.
If you have any questions, call 0031 (0)35-6958090.