Well, I've been to the Mithraeum - when I found it, Bloomberg have spent a fortune on doing really, really, well but clearly employed one of those designers who think that signage should be discreet, I had a little trouble with the labelling in the very swanky loos
it doesn't actually take long, we were in there almost exactly an hour, and it would have take less time with less people to talk to . At ground level there is a contemporary art display, currently four large sculptures and a wall of objects form the Walbrook dig behind glass. This is excellent, no labels, you pick up an iPad which has a picture of the display on it, touch the object you are interested in, and it shows you some relevant information ,ery easy to read
Then you go downstairs to a waiting area where there's some audio (and a bit of visual) telling you about the cult of Mithras, Then yo are invited to go in batches down another level to the actual temple (it's quite small, more a chapel) and there's a bit of son et lumiere to give you a feel for what it would be like in use, and you get time to walk round and look at it.
Afterwards we went and had a peep at St Stephen Walbrook almost opposite, a lovely Wren church, no used in the round. Then we went for a sandwich,
Nice outing, but I am now tired!
Yes, it sounds as if there has been an copy cat terror attack at London Bridge