Which two structures were first built in the town

The first things built were a prison-house and a cemetery.

The founders of a new colony, whatever Utopia of human virtue and happiness they might originally project, have invariably recognized it among their earliest practical necessities to allot a portion of the virgin soil as a cemetery, and another portion as the site of a prison. In accordance with this rule, it may safely be assumed that the forefathersof Boston had built the first prison-house somewhere in the vicinity of Cornhill, almost as seasonably as they marked out the first burial-ground, on Isaac Johnson's lot, and round about his grave, which subsequently became the nucleus of all the congregated sepulchres in the old churchyard of King's Chapel.