Hello! So same as 10's TARDIS, the TARDIS is actually considered a vehicle rather than a location. So the subarchway must be to a specific location that they know the TARDIS will be in, then they can pull the TARDIS out as they see fit. What would the specific location you would like to have the subarchway to be?

Additionally, please provide a short description of the location. As stated in the post, a small paragraph must be provided for players (not just a link).