Field Marshal Bernard Montgomery argued through August 1944 for a concentrated thrust across the Rhine rather than a broad advance on Germany. The plan that emerged, Operation Market Garden, would drop three Allied airborne divisions along a single highway through the Netherlands. The US 101st Airborne would take the bridges around Eindhoven, the US 82nd Airborne the crossings at Nijmegen, and the British 1st Airborne the farthest objective: three bridges over the Nederrijn at Arnhem. The British XXX Corps, racing up the corridor from Belgium, would relieve each in turn and be across the Rhine within two days. If it worked, the war in Europe might be over by Christmas. The 1st Airborne Division was commanded by Major-General Roy Urquhart and reinforced by the Polish 1st Independent Parachute Brigade under Stanislaw Sosabowski. Brian Urquhart, an intelligence officer on Lieutenant-General Frederick Browning's staff, brought aerial reconnaissance photographs showing German armor near Arnhem. Browning had him sent on sick leave.

The first lift came in unopposed at 12:40 on Sunday 17 September. The American IX Troop Carrier Command had refused to attempt a closer drop zone, so the paratroopers landed up to 8 miles from the bridge and had to march in. Two of the three battalions in the lead brigade were stopped almost immediately by a thin blocking screen of SS training battalions under Sepp Krafft. The 9th SS Panzer Division Hohenstaufen, which the Allies had been told was not there, organized a kampfgruppe within hours and pushed a defensive line into Oosterbeek, sealing the western edge of Arnhem. Only the 2nd Parachute Battalion under Lieutenant Colonel John Frost slipped along the river road to the centre of the city. At dusk they reached the northern ramp of the road bridge with about 740 men. They could not take the southern end. A German attempt to rush across at 09:00 the next morning cost the SS Reconnaissance Battalion 12 of 22 armored vehicles and over 70 men killed including the battalion commander Viktor Graebner.

The British radio sets failed almost immediately, defeated by the wooded terrain north of the river. For nine days, Urquhart's headquarters could not reliably reach his battalions, Browning's headquarters at Nijmegen, XXX Corps, or England. Carrier pigeons were flown back to Britain to report. Urquhart himself, trying to find his subordinates on day one, was cut off in a Dutch family's attic for two days. The 1st and 3rd Parachute Battalions, joined later by the 11th and the 2nd South Staffordshires, tried four times to break through the German blocking line and reach Frost. By midday on Tuesday 19 September the four battalions had disintegrated, leaving about 500 men to retreat west toward what would become the Oosterbeek perimeter. At the bridge, the Germans began systematically destroying the houses Frost's men were holding. He was wounded by a mortar bomb on Wednesday afternoon. A two-hour truce was arranged so the British wounded, Frost among them, could be taken into German captivity. By 05:00 Thursday morning the bridge had fallen.

What remained of the 1st Airborne Division, about 3,600 men, dug into a thumb-shaped perimeter around the Hotel Hartenstein in Oosterbeek with the Rhine as its southern edge. Urquhart's plan was to hold until XXX Corps could break through from Nijmegen, push across the river, and establish a new bridgehead. The Polish parachute brigade, delayed by weather, finally dropped on the south bank near Driel on Thursday afternoon. They found the Heveadorp ferry gone, sunk by the Dutch ferryman to keep it from the Germans. Improvised river crossings on the next two nights got only a few hundred Poles and British infantry into the perimeter under fire. The 64th Medium Regiment of XXX Corps, firing from miles to the south, kept the German tanks off the perimeter for days, and Urquhart later lobbied unsuccessfully for those gunners to be allowed to wear the airborne Pegasus badge. The supply drops by 38 and 46 Group RAF flew through deepening flak. By Wednesday 20 September only 13 percent of the dropped supplies reached British hands; the Germans had captured British marker panels and were attracting the aircraft to their own positions.

On the night of 25 September, after a Valburg conference decided the division could not be reinforced, the survivors made their way down to the riverbank in muffled boots, in heavy rain. Sappers from the Canadian 23rd Field Company and the British Royal Engineers ferried them across in storm boats and assault craft under German fire that grew through the night. About 2,400 men got over before dawn. The 1st Airborne Division had landed 10,600 men and Poles in the Arnhem area. Some 1,984 Allied soldiers were killed in the nine days of fighting, including more than 1,174 of the British 1st Airborne, 219 of the Glider Pilot Regiment, 92 of the Polish brigade, 368 RAF aircrew, and dispatchers of the Royal Army Service Corps. About 6,400 were taken prisoner. German losses are estimated at at least 1,300 killed. Some 453 Dutch civilians died in the fighting. The 1st Airborne Division did not see combat again as a formation.

The phrase a bridge too far comes from a comment Browning is said to have made to Montgomery before the operation. It became the title of Cornelius Ryan's 1974 book and Richard Attenborough's 1977 film. The road bridge Frost's battalion held was destroyed by US bombers two weeks after the battle and rebuilt almost identically after the war as the John Frost Bridge. The 17th of September is still the official date of commemoration in Arnhem. Veterans, paratroopers, and a thousand Dutch schoolchildren gather at the Airborne Cemetery in Oosterbeek every first weekend of September to lay flowers at the headstones, a ceremony that has not missed a year since 1945. When the Parachute Regiment suggested in 1969 that perhaps the ceremony had run its course, the Dutch refused. They have been keeping the flowers fresh ever since.