Name | Issues/Designs | |||
Tsar Assen Tower
(syn. of Asen's Fortress) |
— | — | d - Tsar Assen Tower 1911 | |
Tsar Assen's Tower
(syn. of Asen's Fortress) |
— | — | d - plane over Tsar Assen's Tower 1940 | |
Tscherwen Fortress
(syn. of Cherven (fortress)) |
— | — | d - Tscherwen Fortress 1966 |