Fiume - Rijeka

The town of Fiume (Rijeka in Croatian) clearly represented an anomaly within the italian fortified system of border defences known as “Vallo Alpino” (Alpine Wall). Not only the town itself was on the very border with Yugoslavia, but this border even passed through the very city center! Italian Fiume lacked its hinterland, being only an enclave connected with Italy by a corridor somewhere only couple of hundred meters wide. Its position was definitely not favourable for any unobserved build-up of italian military forces, and therefore of no use as a starting point of possible push against yugoslav forces in their part of the town (Sussak) and further along the Adriatic coast. On the contrary, Fiume could easily be cut off from the rest of Italy by taking the a.m. corridor.
Ships of the Royal Italian Navy stationed in Fiume and nearby Pola were the initial warranty that the Yugoslavs would not make any “false moves”, but were soon considered inadequate for proper defence of the town.
The Italians have recognized the town`s vulnerable position, and have therefore decided to make it able to defend itself even if cut off from the rest of the country.
Taking into account the impossibility to defend that narrow connecting corridor against any significant yugoslav strike, the Italians only put meters upon meters of barbed wire along it (10-12 m wide), reinforced only by field type MG and AT positions, but all the access ways that led towards this corridor were (wherever possible) appropriately blocked – there was total of 10 blockades, with variety of field type and reinforced field type MG and AT positions.
Steep slopes of hills surrounding the town, especially those on the right bank of Fiumara (Eneo, Rjecina) hardly offered any passage to the possible attacker. Rather, those hills along the border with Yugoslavia to the North-East contributed to the defence of the town, being strongly fortified with permanent concrete or underground fortifications, making Fiume one of the strongest points along the “Vallo Alpino”, and definitely the strongest point along the 220 km long italian border with Yugoslavia.
The scale of fortification efforts and this “special attention” that was given to the town of Fiume can be clearly seen by the fact that along the line approximately 4 km long, it was planned to build 8 forposts with 10 forts (“opere”), with at least 60 combat blocks altogether!
When the war broke out on April 6th 1941, two forposts (4 opere, 27 combat blocks) were completed, with 6 others being in various stages of construction, ranging from mere excavation to almost complete. The use of labour brought from Italy (rather than local one) under strict control of fascist party, together with tremendous care devoted to camouflaging of the combat blocks resulted in forts that blended with surroundings so well that they were almost impossible to locate except from point blank range.
The operational forposts were designated “Caposaldo S. Caterina A” and “Caposaldo S. Caterina B”, located on S. Caterina hill above Fiume on the right bank of Fiumara river (the very border with Yugoslavia), consisting of 2 opere each. The Italians usually built their border fortifications in two more or less parallel lines along the border, but the very nature of geographic position of the town of Fiume – an enclave between Yugoslav mainland and Adriatic sea, connected with Italy only by a corridor approx. 1 mile wide - prevented them from having proper depth of defence in Fiume area. Therefore, the forts of this Fiume “Zona di sicurezza” were much stronger than the rest of border forts in this area.
The distance of some 300 meters between “Caposaldo”s A and B was defended by so-called “mid-forpost” of reinforced field type positions that included well camouflaged separate concrete HMG and LMG bunkers and underground shelters for the crews and ammo.
However, the construction of a full scale “opera” was underway in the same location from the late thirties. This “Montecroce Est” opera remained unfinished.
Farther to the West, on top of the Mt. Lesco hill where the border line made sharp turn towards the coast, was large fort “Mt. Lesco”.

There were two other locations farther to the South where, however, the construction of two underground forts did not advance past the excavation stage, or covering the corridors with concrete: Drenova and Dorcici.

The favourable results of the April `41. campaign against Yugoslavia halted or slowed down the progress of work on border fortifications, since the border moved farther to the East, but the hills around the annexed town of Sussak were chosen as the sites for new forts. However, the forts of Tersatto and S. Anna above Sussak remained unfinished.