The Battle of Fardykambos (Greek: Μάχη του Φαρδύκαμπου), also known as the Battle of Bougazi (Μάχη στο Μπουγάζι), was fought between the National Liberation Front (EAM-ELAS) of the Greek Resistance against the Italian troops during the Axis Occupation of Greece. The battle was notable for the large-scale and spontaneous participation of the local populace, and of officers from other groups and organizations, including right-wing rivals to ELAS.

The three-day battle began with the successful ambush of an Italian transport column on 4 March 1943. The Italian battalion garrisoning the nearby town of Grevena came to the column's rescue, but was halted before the town of Siatista by Greek partisan forces. The Greek forces continued to swell as reserve officers and ordinary civilians flocked as volunteers to the sound of battle, reaching a force of some 2,000 men. By nightfall on 5 March, the Italian battalion had been surrounded by the Greeks, and after incessant harassment and attacks over the following day, was forced to surrender on the night of 6/7 March. Many weapons and supplies, including field artillery, were acquired by the Greeks, and over 550 Italian troops became prisoners of war. The battle led to the liberation of Grevena from Italian occupation a few weeks later, and was a major sign of the growth of the Greek partisan movement, and the collapse of Italian rule over rural Greece.

On 6 April 1941, following a botched Italian invasion in October 1940, Nazi Germany invaded Greece through Bulgaria and Yugoslavia. The Greek capital Athens fell on 27 April, and by June, after the capture of Crete, all of Greece was under Axis occupation. Most of the country was left to the Italian forces, while Bulgaria annexed northeastern Greece and German troops occupied the strategically most important areas. A collaborationist government was installed, but its authority with the Greek people was minimal, and its control over the country compromised by the occupation authorities, who created a patchwork of separate jurisdictions. As early as the autumn 1941, the first stirrings of a resistance movement were registered, with attacks on isolated Gendarmerie stations in Macedonia in northern Greece. The establishment of large-scale resistance organizations, most notably the communist-dominated National Liberation Front (EAM) and its military wing, the Greek People's Liberation Army (ELAS), which proceeded apace in 1942, began to challenge not only the collaborationist government's organs, but also the Italian occupation troops.

On 29 January 1943, ELAS partisans entered the Macedonian town of Siatista, attacked the local Gendarmerie station and disbanded it. Lieutenant Thomas Venetsanopoulos and ten more gendarmes even joined the ELAS forces. Siatista thus became the first town in occupied Greece to be liberated. A few days later, ELAS forces clashed with an Italian Army company near the village of Snichovo (modern Despotis). As a result, the Italians engaged in reprisals against the civilian population: in the provincial capital of Grevena, the Italian battalion garrisoned there executed seven civilians, while the Lancieri di Aosta cavalry regiment burned villages in the area of the Kamvounia mountains.

The battle comprised two different but connected engagements: an ambush on 4 March, at the pass of Vigla, against an Italian transport column, followed by the second and main battle at Fardykambos, on 5–6 March, against the Italian garrison of Grevena that set out to relieve the transport column.

On 4 March, ELAS forces from Siatista, augmented with Reserve ELAS members from the surrounding villages, some 200–250 men in total, ambushed an Italian convoy heading for Grevena from Korçë via Florina and Kozani. The ambush took place in the narrow pass of Bougazi between the mountains of Sniatsiko and Bourino, at the location known as Vigla, some 3 km from Siatista itself. The partisans were armed with shotguns and antiquated Gras rifles, axes, and damascened knives, but were able to knock out the first and ninth lorries in their opening salvo, trapping the bulk of the convoy; only the tenth lorry, at the rear of the column, managed to turn around and escape. The battle lasted for three hours, and was ended when the partisans closed in for hand-to-hand combat, whereupon the Italians surrendered. Of the 180 Italians in the convoy, 15 lay dead and 34 were wounded, who were handed over to Red Cross representatives. The rest were taken prisoner. The partisans suffered only three lightly wounded. The lorries, five of which were in running order, contained large quantities of food, a mortar, a heavy and ten light machine guns, as well as rifles and ammunition were captured and carried off.

In the meantime, when the convoy became overdue in Grevena, the local commander, Perrone Pasconelli, sent a company in four lorries to look for it, but it was halted by hastily drawn together ELAS reserves, comprising mostly old men and very young boys, at the Aliakmon River bridge. As a result, early in the afternoon, the rest of the Grevena garrison set out, 600 men in total, leaving behind only a skeleton guard. The arrival of night forced the Italians to halt at the site of the earlier skirmish near the village of Agios Georgios, while ELAS mobilized every available man from Vogatsiko, Tsotyli, and Neapoli, and the local inhabitants of Siatista and the neighbouring villages flocked to assist them, raising their strength to some 600 men. Among the people flocking to the sound of the battle were also many regular and reserve officers who were not members of ELAS; some were even members of right-wing organizations such as EKA. Nevertheless, the ELAS command welcomed them and assigned them various commands. The same happened with nearby Gendarmerie units that flocked to the battle, including the entire Gendarmerie garrison of Servia, under its commander Charalambos Koutalakis, as well as the guard installed by the Germans at the Aliakmon bridge.

On the morning of 5 March the Italians managed to cross the Aliakmon bridge and reach the defile where their supply convoy had been captured. Around noon, the Italians regrouped at a site near the crossing of the Kozani-Grevena-Kastoria road, where there were many cultivated fields and vines, known as Fardykambos. In the afternoon, the Italians attacked the partisan positions on then heights south of Siatista, using the three mountain cannons they had brought with them to great effect. Despite heavy resistance, the Italians advanced with determination, reaching the outskirts of the lower town of Siatista. At this point, the ELAS leadership decided to outflank the Italians, sending one group, under Tasianopoulos, Skotidas, and Foteinos, to attack them from the west, while 25 men from the village of Polylakkos, under Second Lieutenant Dimitrios Papagianopoulos, crossed the Aliakmon by swimming, and attacked the Italian battalion's command post. At the same time, the ELAS detachment from Grevena attacked the Italian battalion from the south, forcing it to fall back to Fardykambos. At one point, the partisans even came close to the Italian commander's tent, until nightfall forced an end to combat.