The address is:
3072 AP – Rotterdadam
tel: +31 (0)10 206 7600
The hotel is very easily reachable by metro or tram from the brand new Rotterdam Central Station (about 10 minutes). The hotel is also reachable by watertaxi.
Note that Rotterdam also has its own airport Rotterdam-the Hague Airport with about 40 direct connections, mainly in Europe.