The Vatican will release a new postage stamp, and Pope Francis will offer a special catechetical session for volunteer workers, as part of the September celebration of the canonization of Mother Teresa of Calcutta.
Anywhere on Vatican territory that has a post box.
That is to say, at the post office in St Peter’s Square, and in the boxes available at some of the extra territoriale institutions such as the major basilicas in Rome.
As a point of interest, many people who have need to post items in Rome will choose Vatican post above the Italian post service - it’s generally quicker and more reliable.
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