HS2 Ltd estimate the number of properties within the safeguarding zone for HS2 phase one, which are not to be demolished as a result of construction or operation, is 3730. Of this number, some 3,450 are within sub-surface safeguarding, which normally means that the route is in tunnel at that point. Note: Safeguarding numbers were calculated using Royal Mail data cross matched with HS2 Ltd's mapping information.