Room 21407 is in building 21 on the fourth floor to get to building 21 from here you follow the road that goes under building 10 then turn left and walk along the road until building 9 and 6. And go past between the building 9 and 6. Take the first on the right and turn left. The building 21 is on your right. Then go to get on the lift. Go up to the fourth floor. After you come out of the lift, turn left, go though some doors and room 21407 is the left.