The 2nd Engineer Regiment () is a military engineering regiment of the Italian Army based in Trento in Trentino. The regiment was formed in 1860 and is currently the oldest active engineer regiment of the Italian Army. Since 1954, the unit has been assigned of the 4th Alpine Army Corps and has therefore a strong association with the Italian Army's mountain infantry speciality, the Alpini, with whom the regiment shares the distinctive Cappello Alpino. The regiment is the engineer unit of the Alpine Brigade "Julia" and specializes in mountain combat.

In 1860, the Royal Sardinian Army split the Sappers Regiment into the 1st Sappers Regiment and 2nd Sappers Regiment, which were both tasked with training sappers units. During the same year the regiment's companies fought in the Sardinian campaign in central and southern Italy and in 1866 in the Third Italian War of Independence. In 1867, the two sappers regiments were merged into the Sappers Corps, which, in 1874, was disbanded so the two regiments could be reformed. The 2nd Engineer Regiment provided personnel for First Italo-Ethiopian War and two sappers battalions for the Italo-Turkish War. During World War I the regiment's battalions and companies fought in all sectors of the Italian Front, and on the Albanian Front, and Western Front. In 1920, the regiment was disbanded. In 1922, the Royal Italian Army formed the 1st Army Corps Engineer Grouping, which in October 1926 was renamed 2nd Engineer Regiment. During the Second Italo-Ethiopian War and World War II the regiment's depot formed engineer battalions and smaller units, which deployed with divisions and corps to the fronts of the war. After the announcement of the Armistice of Cassibile on 8 September 1943 the regiment was disbanded by invading German forces.

In 1954, the unit was reformed as 2nd Engineer Grouping and assigned to the IV Army Corps. In 1955, the grouping was renamed 2nd Engineer Regiment. In 1975, the regiment was disbanded and the regiment's II Miners Battalion became an autonomous unit, which was renamed 2nd Miners Battalion "Iseo". After the regiment was disbanded, the flag and traditions of the 2nd Engineer Regiment were transferred to the 2nd Miners Battalion "Iseo", which also received the traditions of the 2nd Miners Regiment. The battalion was based in Bolzano and assigned to the 4th Alpine Army Corps's Engineer Command. In 1995, the 2nd Engineer Regiment was reformed by renaming the 1st Pioneer Regiment in Trento, whose battalion was renamed Sappers Battalion "Iseo". In 2002, the regiment was transferred from the Alpine Troops Command to the Alpine Brigade "Julia". The regiment's anniversary falls, as for all engineer units, on 24 June 1918, the last day of the Second Battle of the Piave River.

History Italian Wars of Independence On 29 September 1848, during the First Italian War of Independence, the Royal Sardinian Army formed a Sappers Regiment in Alessandria, which consisted of a staff and two battalions, each of which fielded four sappers companies and one miners company. In May 1859, during the Second Italian War of Independence, Sardinian forces occupied the Grand Duchy of Tuscany, the Duchy of Parma and Piacenza, the Duchy of Modena and Reggio, and the Papal Legations of the Romagne. On 12 July 1859, the war ended with the Armistice of Villafranca, which called for the rulers of the occupied territories to be restored to their thrones. However, neither the Kingdom of Sardinia nor the Sardinian installed governments in the occupied territories wished for a return of the rulers. On 30 November 1859, the Duchy of Parma and Piacenza, the Duchy of Modena and Reggio, and the Papal Legations of the Romagne were united under the Royal Government of Emilia, which, on 1 January 1860, was redesignated as the Royal Provinces of Emilia. On 11 and 12 March 1860, the Royal Provinces of Emilia and the Grand Duchy of Tuscany voted in a plebiscite for annexation by the Kingdom of Sardinia. On 18 March 1860, the annexation act was presented to Victor Emmanuel II and the annexation completed. On 2 May 1860, the Royal Sardinian Army incorporated two Tuscan and eight Emilian sappers companies and, on the same day, the Sappers Regiment, which at the time consisted of five battalions, ceded some of its battalions to help from the 2nd Sappers Regiment in Piacenza. Consequently, the Sappers Regiment was renamed 1st Sappers Regiment.

The 2nd Sappers Regiment consisted of a staff, three battalions of four sappers companies per battalion, and a depot. Immediately after its formation, Garibaldi's Expedition of the Thousand triggered the Sardinian campaign in central and southern Italy, which led to the Siege to Gaeta. During the siege the regiment's 3rd Sappers Company and 7th Sappers Company distinguished themselves, for which both companies were awarded a Bronze Medal of Military Valor. After the surrender of Gaeta, the Kingdom of Sardinia annexed the Kingdom of the Two Sicilies and most of the remaining Papal Legations. On 17 March 1861, King Victor Emmanuel II proclaimed himself King of Italy.

After the annexation of the Kingdom of the Two Sicilies the 2nd Sappers Regiment provided troops for the suppression of the anti-Sardinian revolt in Southern Italy. In 1866, the regiment's companies fought in the Third Italian War of Independence. On 25 August 1867, the 1st and 2nd sappers regiments merged to form the Sappers Corps, which had its headquarters in Casale Monferrato and consisted of a staff and 28 sappers companies. In 1870, the 1st, 2nd, 4th, 10th, and 25th companies participated in the capture of Rome.

On 31 December 1873, the Sappers Corps and the 1st Artillery Regiment (Pontieri) were disbanded. The next day the Sappers Corps' staff in Casale Monferrato was used to form the 2nd Engineer Regiment, while the staff of the 1st Artillery Regiment (Pontieri) in Pavia was used to form the 1st Engineer Regiment. The 2nd Engineer Regiment retained 13 sappers companies, two Ferrovieri companies, one train company, and the depot of the disbanded Sappers Corps, while transferring 14 sappers companies and one Ferrovieri company to the 1st Engineer Regiment. In turn the 2nd Engineer Regiment received four Pontieri companies from the 1st Engineer Regiment. On 1 July 1874, the regiment formed a second train company, followed by third train company on 1 January 1876. On 1 January 1877, the regiment formed the 14th Sappers Company (Lagunari), which was based in Venice and tasked with operating in the Venetian Lagoon, Marano Lagoon, and Grado Lagoon.

On 1 January 1883, the regiment formed three sappers companies, three telegraphers companies, and one train company. On the same day, the regiment ceded its four Pontieri companies, the 14th Sappers Company (Lagunari), and a train company to help form the 4th Engineer Regiment. On 1 November of the same year, the regiment ceded three telegraphers companies, two Ferrovieri companies, two sappers companies, and a train company to help form the 3rd Engineer Regiment. On 1 November 1887, the regiment formed four new sappers companies. On 1 November 1895, the regiment ceded six sappers companies to help form the 5th Engineer Regiment (Miners). On the same day, the regiment was renamed 2nd Engineer Regiment (Sappers). At the time the regiment consisted of a staff, four sappers brigades of three sappers companies each, two train companies, and a depot. During the same year the regiment provided six officers and 243 enlisted for units deployed to Eritrea for the First Italo-Ethiopian War. In 1910, the brigades were renamed battalions. In 1911–12, the regiment's I Battalion and II Battalion were deployed to Libya for the Italo-Turkish War. In July 1912, the regiment formed a fifth sappers battalion.

World War I During World War I, the regiment's depot mobilized 42 sappers battalion commands, 122 sappers companies, 52 bridge sections, 31 divisional cableway sections, six firefighters sections, five cableway sections for alpine groups, one territorial militia battalion command and six territorial militia companies, and 11 army corps engineer parks. The battalions and companies formed by the regiment fought in all sectors of the Italian Front, and on the Albanian Front and Western Front.

Interwar years In April 1919, the regiment's LII Engineer Battalion was assigned to the Royal Italian Army's Expeditionary Force in the Eastern Mediterranean, which on 29 April 1919 occupied Antalya, and on 11 May 1919 Fethiye, Bodrum and Marmaris in Anatolia. Italy claimed the area as its sphere of influence as per the Agreement of Saint-Jean-de-Maurienne, which partitioned the Ottoman Empire. The Treaty of Sèvres confirmed an Italian zone of influence in the area and the Italian occupation of Antalya continued until October 1922 when Italy removed its troops from Anatolia. On 31 March 1920, the 1st Engineer Regiment (Sappers) and 2nd Engineer Regiment (Sappers) were disbanded and the next day, on 1 April 1920, the two regiments' companies were used to form an Army Corps Sappers Battalion for each of the Royal Italian Army's army corps.

On 1 October 1922, the Royal Italian Army formed the 1st Army Corps Engineer Grouping in Turin. The grouping received a Sappers Battalion and a Telegraphers Battalion, which had been formed on 1 April 1920 for the I Army Corps. The grouping also received a miners company from the disbanded Miners Engineer Regiment. After its formation the grouping consisted of a command, a sappers-miners battalion, a telegraphers battalion, which included six dovecotes located in Turin, Cuneo, Exilles, Fenestrelle, Vinadio, and Alessandria, a photo-electricians company, and a depot. In 1924, the grouping moved from Turin to Casale Monferrato.

In 1926, the Royal Italian Army formed an army corps command in Alessandria, which was designated II Army Corps. Subsequently, the 1st Army Corps Engineer Grouping was transferred from the I Army Corps to the II Army Corps, and consequently, on 11 October 1926, the grouping was renamed 2nd Engineer Regiment. Afterwards the regiment consisted of a command, a sappers-miners battalion, a cableway battalion, a telegraphers battalion, a depot, and six dovecotes located in Alessandria, Cuneo, Genoa, Vinadio, Tende, and Nava. The dovecotes in Turin, Exilles, Fenestrelle were transferred to the newly formed 1st Engineer Regiment, while the 7th Engineer Regiment ceded the dovecote in Nava to the 2nd Engineer Regiment. In February 1928, the regiment ceded a sappers-miners company to help form the 11th Engineer Regiment.

On 1 February 1931, the regiment reorganized its Cableway Battalion as Miners-Cableway Battalion, which was transferred on 28 October 1932 to the newly formed 1st Miners Regiment in Novi Ligure. On the same date, the regiment received the I Radio-Telegraphers Battalion of the disbanded 2nd Radio-Telegraphers Regiment.

In 1935, the regiment mobilized the XIV Cableway Battalion, an autonomous cableway company, a connections company, a sappers company, a mixed engineer company, a water platoon, a cableway replacements company, and two firefighting sections for the Second Italo-Ethiopian War. In January 1937, the telegraphers and radio-telegraphers battalions were renamed connections battalions.

World War II During World War II the regiment's depot in Casale Monferrato mobilized the following units:

Command of the 5th Engineer Grouping IV Mixed Engineer Battalion (for the 4th Alpine Division "Cuneense") V Telegraphers Battalion V Marconisti Battalion V Engineer Battalion XXVII Engineer Battalion LIV Mixed Engineer Battalion (for the 54th Infantry Division "Napoli") 5th and 6th mobile dovecotes and many smaller units