Question: On what date did the Soviets attack the 3rd Panzer Army with 700 tanks?
About the article "Operation Barbarossa", section "Phase 2: Battle for Smolensk (3 July – 5 August 1941)".

Candidate passages:
On commencement of Operation Barbarossa, the group was a part of Army Group North, and consisted of the XLI Panzer and LVI Army (motorized) Corps which comprised three panzer and two motorized infantry divisions respectively, altogether equipped with 631 tanks.
Acting as the armored spearhead for Army Group North in the opening phase of Operation Barbarossa, it crossed the Neman River, where the XLI Panzer Corps was counter-attacked by 300 Soviet Tanks near Raseiniai.
In a 4 day battle, the Germans encircled and destroyed the Soviet Armor.
The LVI Panzer Corps seized the Dvina bridges and began their advance towards Leningrad.
The Soviets formed a bitter defense around Leningrad and Hitler reinforced 4th Panzer Army with the 3rd Panzer Army and it crept up to 7 miles of the city.
However, Hitler re-called both Panzer Armies and transferred them to Army Group Center for an all-out offensive around Moscow.
The operation called for the 3rd and 4th Panzer Army to attack Moscow from the North.
The 4th Army would attack through the center and 2nd Panzer Army to attack from the south.
But due to the cold weather, deteriorating supply situation and bitter Soviet resistance, only the 4th Panzer Army made any headway against the Soviets and reached to about 15 miles of Moscow.
Exhausted, it was halted at the gates of Moscow and then pushed back 200 miles by the Soviet counteroffensive launched in December 1941. 
In July and August 1943 the Soviets succeeded in stopping the German offensive Operation Citadel into the Kursk Salient and counterattacked towards Orel and Kharkov.
In tandem with the offensive into Ukraine another offensive, the Smolensk Operation, was launched against Army Group Centre between August and October 1943.
The attacks made slow progress but were successful in recapturing Smolensk and the important rail junction at Nevel, forcing the German line back on a broad front; however the attack foundered on the strong German defensive works in the Vitebsk-Orsha-Mogilev area (the Ostwall defensive line).
March 1943 order of battle 3rd Panzer Army, 9th Army, 4th Army, 2nd Panzer Army, 2nd Army April 1943 order of battle 3rd Panzer Army, 4th Army, 2nd Panzer Army, 2nd Army, z. Vfg.
9th Army July 1943 order of battle 3rd Panzer Army, 4th Army, 2nd Panzer Army, 9th Army, 2nd Army  
The battle of Târgu Frumos was a series of engagements and smaller combats over several days during which armoured forces of the Wehrmacht LVII Panzer Corps, in particular of the Grossdeutschland Division and 24th Panzer Division, engaged the Red Army’s 16th Tank Corps of the 2nd Tank Army, which was also attacking from the north.
One unit's experience in the opening hours of the battle was described as such:"(1st Battalion), P(an)z(er)Gr(enadier) R(e)g(imen)t G(ross)D(eutschland) and its Romanian allies occupied a well wired-in and T-Mine-strewn line running to the right of 3.
"Totenkopf's" positions.
The Soviets advanced in great waves, their tanks and infantry mixed together.
Moving much faster than the Germans had anticipated, they overwhelmed...(the 1st Company), wiping it out to the last man.
While (the) temporary battalion commander...attempted to halt and repulse the Soviets with what was left of his battalion, the Romanians to the left of (the 2nd Company) cowered in their trenches like "herrings", as (the) company commander...later recounted.
Indeed, the Romanians seemed to have reached an unofficial cease fire with the enemy.
That night the Luftwaffe succeeded in mounting an air strike in the enemy rear area, to no avail.
The next morning the Soviets resumed their attack, preceding it with a bombardment of phosphorus shells.
Over 100 enemy tanks and assault guns advanced against (the 3rd Platoon).
With his Romanian artillery remaining inactive, (the 3rd Platoon of the 2nd Company) could count only on the support of three...(assault guns) and the four 15cm Nebelwerfer multiple rocket launchers of (the 10th Company, Panzer Artillery Regiment Grossdeutschland).
(The 2nd Company) was soon back to the Nebelwerfer's position where it formed a 'hedgehog' defense...and a handful of...men then managed to gain the temporary safety of the railway embankment in their rear.
His battalion scattered, (the 1st Battalion commander) sent (the 2nd Company commander) with four SPW's to cover the wide open left flank, completely vulnerable when the Romanians abandoned their positions.
Although the enemy had not made any deep penetrations, the tension of the past two days had exhausted the Panzergrenadiers.
"Suddenly...four T-34s were in among the SPWs when, as if by magic, tanks and assault guns of the SS-Division "Totenkopf" appeared.
Before a single T-34 could train its gun, all had received direct hits."
Immediately thereafter Oberst Hans-Ulrich Rudel's Ju87 Stukas led off a counter thrust by "Totenkopf's" Panzerregiment, accompanied by...four SPWs.
The Panzergrenadiers took a measure of revenge for what they had endured over the past 48 hours...before being pulled out of the line to regroup and refit.
"Despite initial successes of the Soviet attack, a series of counter-attacks managed to halt the Soviet offensive.
The battle reduced Soviet tank strength to a point where a continued attack into Romania was not possible.
In the three days of fighting, the Wehrmacht LVII Panzer Corps (mainly Grossdeutschland and 24th Panzer Division) and LII Army Corps defeated the Soviet force and claimed the destruction of over 350 Soviet tanks, ca.
100 of these claimed by 24th Panzer Division.
During the battle, Hasso von Manteuffel, commander of the Grossdeutschland division, first encountered the new Soviet Stalin tank, "It was at Târgu Frumos that I first met the Stalin tanks.
It was a shock to find that, although my Tigers began to hit them at a range of 3,000 metres, our shells bounced off, and did not penetrate them until we had closed to half that distance.
But I was able to counter the Russians' superiority by manoeuvre and mobility, in making the best use of ground cover."
Manteuffel also noted that the Stalin tanks had several "disadvantages: slow, not manoeuvrable enough; as well, in my opinion their crews were not sufficiently familiar with the tank."
Not all of the German units, which had to be reinforced across the bridges at Stettin were ready on the planned start date of February 15.
Nevertheless a part of the central corps, the SS Division Nordland, attacked towards Arnswalde that day.
Initially the offensive was successful; the opposing forces of 61st Army were taken by surprise and the German spearhead reached the besieged outpost of Arnswalde and relieved its garrison.
A general attack opened the following day.
The central corridor to Arnswalde was widened by the III SS Panzer Corps, pushing part of the Soviet front eight to twelve kilometers back.
However, the attack by the XXXIX Panzer Corps was unable to reach the Plöne Lake due to resistance by the Soviet 2nd Guards Tank Army, stalling some 70 kilometers from Küstrin after pushing the Russians out of Sallenthin and Muscherin, reoccupying some land on the eastern shore of Lake Madü, and recapturing Pyritz.
"Gruppe Munzel" pushed some four kilometers to Liebenow, while the III SS Panzer Corps advanced about a kilometer to Reetz.
Numbers of Soviet tanks and antitank guns were destroyed by German Tiger II heavy tanks, but the German heavy tanks also took losses.
In general, German progress was hindered because of strong Soviet resistance and a thaw that created muddy conditions in which the heavy German tanks performed poorly.
Soviet T-34s, on the other hand, with up to twenty-five percent lower ground pressure, had excellent mobility even in those conditions.
On February 17, General Wenck, commander of the offensive, was seriously injured in a car accident.
While being driven back from a briefing in Berlin, he took over driving from his driver (who had been on duty for 48 hours) and then himself fell asleep at the wheel.
He was replaced by Hans Krebs, but command initiative had already been lost.
Later that day, Zhukov threw the 3rd Shock Army, which had redeployed from the area of Jastrow, into a counter-attack and the German offensive stalled.
Army Group Vistula halted "Sonnenwende" on February 18.
On February 19, Zhukov initiated a counter-offensive aimed at the capture of Stettin using the 61st and the 2nd Guards Tank Armies as well as the 7th Guards Cavalry Corps.
However it stalled in the heavy street fighting during the re-capture of Arnswalde.
There was no immediate German withdrawal, but the German command decided on February 21 to withdraw the headquarters of the XXXIX Panzer Corps as well as the "Führer-Grenadier", "Führer-Begleit", "Holstein", and 10th SS Panzer Divisions westward behind Army Group Center, practically ensuring that eastern Pomerania would fall to the Soviets.
Zhukov's commitment of the 70th Army into an attack on February 23 spurred a retreat with the German forces losing or abandoning many tanks.
On February 24, Marshal Rokossovsky's 2nd Belorussian Front renewed the offensive into Pomerania, opening a wide gap in German lines west of Grudziądz and moving almost fifty kilometers (30 miles) forward, further reducing the cohesion of German defenses. 
After the Ardennes offensive failed, the SS Divisions involved were pulled out and refitted in Germany in preparation for Operation Spring Awakening, with top priority for men and equipment.
The replacements were a mixed group of raw recruits and drafted Luftwaffe and Kriegsmarine personnel no longer needed by their own branch of service, as they had no aircraft or ships to serve in.
The 6th SS Panzer Army would again take the lead, with the I SS Panzer Corps (1 SS "Leibstandarte" and 12 SS "Hitlerjugend") and the II SS Panzer Corps (2 SS "Das Reich" and the 10 SS "Frundsberg").
Also present but not part of the 6th SS Panzer Army was the IV SS Panzer Corps (3 SS "Totenkopf" and 5 SS "Wiking").
This was the first time that six SS Panzer Divisions took part in the same offensive.
As planned, the offensive got under way on 6 March 1945, spearheaded by the 6th SS Panzer Army.
The attack surprised the Soviets, and impressive gains were made for an offensive launched at such a late date in the war.
However, once the Soviets realized that elite SS units were involved, they took the German offensive seriously, utilizing 16 rifle divisions, two tank corps (with some 150 tanks), and two mechanized corps, in direct support just behind the front line south west of Lake Balaton.
The Soviets had been building up their forces for their own offensive along the Danube valley, which meant the 6th SS Panzer Army's attack was confronted by an overwhelming Soviet force of more than 1,000 tanks, which ground the German advance to a halt.
By 14 March the attack was in serious trouble.
The advance of the 6th SS Panzer Army, while impressive, was well short of its targets.
Two days later, the Soviets launched a massive counterattack, which drove the 6th SS Panzer Army back to its start line within 24 hours.
All six of the Waffen-SS divisions suffered grievously during Spring Awakening, and by the end most were below 50 per cent strength without much prospect of reinforcements to replace their losses.