The Battle of Messines, fought from 7 to 14 June 1917, was one of the most carefully prepared Allied operations of the First World War. At 3:10 a.m. on 7 June, nineteen huge underground mines exploded beneath German positions along the Messines-Wytschaete Ridge. British, Australian and New Zealand infantry then advanced behind a precisely coordinated artillery barrage and captured the ridge. The attack succeeded because it combined years of tunnelling, detailed rehearsal, counter-battery artillery, engineering and limited objectives.

Messines is often introduced through the spectacular mine explosions, but the real lesson is preparation. The mines were only one part of a complex system. Today the ridge is one of the best areas in Flanders for understanding underground warfare, New Zealand's Western Front story, the Australian 3rd Division under John Monash, Irish participation and the way a successful 1917 operation prepared the southern flank for Third Ypres.

Why the ridge had to be captured

Messines and Wytschaete sit on high ground south of Ypres. German forces had held much of this ridge since 1914. From it they could observe Allied positions and threaten the southern flank of any future offensive east from Ypres.

Before the British could launch the much larger Flanders offensive planned for summer 1917, Plumer's Second Army was tasked with removing the ridge. This was therefore both an independent battle and a preparatory operation for Third Ypres.

Two years of preparation underground

The mining system beneath Messines was not created in a few weeks. Tunnelling companies worked for many months, often at great depth, driving galleries under the German front line. The work demanded geological knowledge, ventilation, timbering and extreme secrecy.

German tunnellers were also active. If they detected an Allied gallery, they could destroy it with a counter-mine. The underground war therefore involved listening, deception and technical skill as much as brute force.

Why the blue clay mattered

Parts of the Ypres region contain layers of clay suited to deep tunnelling. In the right conditions, galleries could be excavated quietly and remain relatively stable. Tunnellers learned to work through different soils and manage water.

The geology of Flanders directly shaped military possibilities. What happened at Messines was possible because engineers understood the ground beneath the battlefield.

22 mines prepared, 19 explode

New Zealand history records that twenty-two mines were prepared for the operation and nineteen exploded at zero hour. Some had been lost to German counter-mining or were not used.

The detonations ripped apart strongpoints and created enormous craters. The Australian War Memorial estimates that the initial blasts caused around 10,000 German casualties. Exact numbers are difficult to establish, but the physical and psychological effect was immense.

Do not make the mines the whole story

The explosions dominate popular memory because they were spectacular. Yet an underground blast cannot capture and hold a ridge. Infantry still had to advance, German artillery still had to be suppressed and captured ground still had to be defended.

Messines worked because the mines were synchronized with artillery, infantry, engineers, logistics and rehearsals.

Plumer and meticulous preparation

General Herbert Plumer had a reputation for careful planning. The Messines assault was rehearsed on model terrain. Routes were prepared. Ammunition was accumulated. Artillery batteries registered targets and attempted to neutralize German guns.

The attack aimed at defined objectives rather than an unlimited breakthrough. This approach foreshadowed the limited-objective methods Plumer would use again in September 1917 at Menin Road, Polygon Wood and Broodseinde.

The artillery plan

Before zero hour British guns had already spent days battering German positions and wire. Counter-battery work attempted to identify and silence enemy artillery. At 3:10, immediately after the mines exploded, the artillery programme shifted to support the infantry.

A creeping barrage moved forward according to a timetable. Infantry followed behind it, using the shell curtain to keep German defenders suppressed until attackers were close enough to assault.

The New Zealand Division and Messines village

The New Zealand Division's objective included the ruined village of Messines. NZ History records that its leading brigades entered the ruins quickly and had cleared the village by about 7 a.m.

The division then continued toward later objectives on the far slope. The speed of the advance reflected preparation and the disruption of German defenders by the mines and artillery.

Samuel Frickleton VC

Lance-Corporal Samuel Frickleton, a Scottish-born New Zealand miner, won the Victoria Cross during the attack. Although wounded, he attacked machine-gun positions with grenades and helped clear resistance near Messines.

His background as a miner gives an interesting human connection with a battle defined by underground engineering, although Frickleton himself was fighting above ground as infantry.

The 3rd Australian Division and John Monash

Messines was the first major battle of the newly arrived Australian 3rd Division, commanded by Major-General John Monash. The division attacked south of the New Zealanders.

For Monash and his men, the battle was a major test. The successful operation helped establish the division's reputation and formed an important step in Monash's later career as one of the Australian Imperial Force's most influential commanders.

Australian losses

The Australian War Memorial records around 6,000 Australian casualties in the wider Messines fighting. This again demonstrates that a successful battle could still be extremely costly.

Many losses occurred after the initial objectives were secured, when German artillery began shelling the crowded captured ridge.

The Irish divisions

The 16th (Irish) Division and 36th (Ulster) Division fought beside one another at Messines. Their participation gained powerful symbolic meaning because the divisions drew heavily from different political and religious traditions in Ireland.

Men who might have been political opponents at home fought in the same operation. The later Island of Ireland Peace Park uses this shared service as a symbol of reconciliation.

Major Willie Redmond

Major William Redmond, an Irish nationalist politician and brother of John Redmond, was mortally wounded during the battle. He was treated by men from the Ulster Division before dying.

His grave near Loker became one of the best-known individual Irish remembrance sites in Flanders. His story complicates simple divisions between nationalist and unionist wartime memory.

The Island of Ireland Peace Park

The round tower at Messines was opened in 1998 as a memorial to the Irish dead and as a symbol of reconciliation. It stands close to the battlefield where the two Irish divisions fought in June 1917.

The memorial should be explained as a late twentieth-century act of memory, not a structure created immediately after the war. Its meaning belongs partly to the Northern Ireland peace process.

The Pool of Peace

Spanbroekmolen crater, now known as the Pool of Peace, was created by one of the great mine explosions. Water filled the crater after the war, producing the quiet pond seen today.

The contrast is powerful, but the crater should be interpreted as a military engineering feature. It marked a specific point in the German defensive line and had to be incorporated into the advancing infantry's plan.

Bayernwald and the German side

Bayernwald preserves a reconstructed German trench system on the ridge near Wijtschate. It includes bunkers, trenches and mine-shaft remains and is one of the best places to understand the defensive side of the battle.

Visiting Bayernwald before the Pool of Peace helps show what the British and Commonwealth armies were trying to destroy and capture.

Why the German army was vulnerable on the ridge

The German position was tactically strong but had a dangerous weakness: years of Allied mining had placed enormous charges beneath key points. The preliminary bombardment also targeted artillery and communications.

When the mines exploded, front-line defenders were hit simultaneously with artillery and infantry assault. Surprise existed at the tactical level even though the Germans knew a major attack was coming.

The Oosttaverne Line

Capturing Messines village was not the final objective. Allied plans pushed onto the far side of the ridge toward the Oosttaverne Line. Reserve formations moved through the first assault waves to extend the gain.

This depth is important because it shows the operation was designed in stages. The ridge crest was a milestone, not the finish line.

Why German shelling caused later losses

Once the ridge was captured, Allied troops concentrated in newly won positions. German artillery recovered and fired onto those areas. Men digging, carrying ammunition and consolidating trenches were exposed.

NZ History notes that much of the New Zealand Division's loss came after the successful initial assault. Victory did not mean safety.

3,700 New Zealand casualties

By the time the New Zealand Division was relieved on 9 June, it had suffered around 3,700 casualties, including about 700 dead. These figures make Messines one of the major New Zealand battles of the Western Front.

The later disaster at Passchendaele often dominates New Zealand memory of Flanders. Messines provides a necessary contrast: a well-planned victory that still cost heavily.

What Messines achieved

The Allied forces captured the ridge and removed a major German observation position. The southern flank of the Ypres Salient improved significantly.

Operationally, the battle demonstrated how preparation, artillery, mining and limited objectives could produce a clear success against a fortified line.

What Messines did not achieve

It did not break the German army in Flanders, and the main Third Ypres offensive did not begin until 31 July. That delay allowed the Germans time to adapt and reinforce.

Historians continue to debate whether the success at Messines could have been exploited more quickly. The important point for visitors is that Messines and Passchendaele were connected but separate operations.

How to visit the battlefield in sequence

Begin on the western side of the ridge and look upward. Visit Bayernwald for the German system, then the Pool of Peace to understand the mines. Continue to Messines village and the New Zealand memorials. Finish at the Island of Ireland Peace Park or nearby cemeteries.

This sequence makes the direction of attack visible and keeps the different national stories within one operation.

The mine that did not explode

Not every mine prepared for Messines detonated in 1917. One famous unused mine at Birdcage near Ploegsteert remains underground, while another charge at Petite Douve was discovered and neutralized by the Germans before the battle.

These surviving stories demonstrate how uncertain underground warfare was. Years of work could be lost if an enemy tunneller heard the wrong sound.

Practical visitor advice

The Messines battlefield is spread across roads, villages, fields and separate memorial sites. A car or guided transport makes it much easier to connect than trying to visit only the village centre.

Some crater paths and rural sites become muddy. Cemeteries and memorials are free, while Bayernwald has separate access arrangements. Check current opening information before planning specifically around the trench site.

Frequently asked questions

When was the Battle of Messines?
The battle began on 7 June 1917 and continued through 14 June, with the decisive assault on the first day.

How many mines exploded at Messines?
Twenty-two mines were prepared for the operation and nineteen exploded at zero hour on 7 June.

Who captured Messines village?
The New Zealand Division's assault included the ruins of Messines village, which were cleared during the morning of 7 June.

How many New Zealand casualties were there?
NZ History records around 3,700 casualties, including about 700 dead, by the time the division was relieved on 9 June.

What is the Pool of Peace?
It is the water-filled Spanbroekmolen mine crater, created by one of the explosions on 7 June 1917.

Why was Messines important before Passchendaele?
Capturing the ridge removed German observation and improved the southern flank before the larger Third Battle of Ypres offensive.