The Belfry consists of Room 62 and Room 63, and a staircase down to the laptop room in the Design & Technology Workshop. You can find the belfry by going up the staircase next to Room 60. If you are a Year 7 or 8, it is indeed unlikely that you will have been up here as you don't take physics yet. The first time up there can feel very Narnia-like, as in a "where on earth did these two classrooms come from that I've never noticed before."
From the belfry, there is a nice view of Waterfoot and depending where you are sat this can be wonderfully distracting.
The BRGS Physics Twitter has made many subtle references to time travel and the belfry... is it possible there is more to these Tweets than what meets the eye?
A time travel device in the belfry would explain why physics lessons always seem to either go very fast or very slow, with no in between.
It goes without saying that the belfry is definitely haunted. Rather than the pleasant physicsy vibes that come from Room 7 and its cat meme posters, the belfry has a more deranged scientist feel. This feeling is probably given off from the old creaky floorboard and peeling paint. Similarly, the walls leading up to the belfry are very bare apart from one sign that says 'no food or drink' - this is probably because a flock of pigeons or a ghost will attack you. The lack of decoration on these walls may also be to hide any hints from lower years knowing what is up there - this is a secret closely guarded by the physics teachers and physics A-level students.