the present building at number 2 ("aeolus 1") was constructed for the national telegraph department ("telegrafverket") in 1868-1870 to the design of architect ludvig hawerman followed by various devastating reconstructions before the restoration of ivar tengbom in 1951-1959. during the middle ages, this was the location of the northernmost defensive tower in the eastern city wall built during the 14th and 15th centuries. as a result of a reconstruction in the mid 18th century, the lot of the salt company building facing slottsbacken was united with the one facing telegrafgränd and in 1782 the building was completely reconstructed again. it was the location for the national archives ("riksarkivet") and the royal academy of letters, history and antiquities ("kungliga vitterhets-, historie- och antikvitetsakademien" (kvhaa) or "vitterhetsakademien" for short) during the period 1848-1863.