25. may 1840, the first day of the operation of the Serbian Post. Report of the Governor of the District of Valjevo to the Ministry of foreign affairs in Belgrade. The letter was posted from Valjevo probably on May 24th 1840, after arrival in Belgrade it had to be sent to Kragujevac where at that time the Ministry was still located. According to the regulations, it transited the Belgrade post office and got the boxed BEOGRAD town postmark and manuscriptly added  “no 8” and “25th of May”. The arrival in Kragujevac on the following day is marked on the reverse. Only 6 more letters with boxed Belgrade are known, but this is the only one used in transit.

Slobodan Mićović – The First Day of the Operation of the Serbian Post, May 25th 1840. – SOFIZ I