Openers Zak Crawley (122) and Ben Duckett (107) stitched a solid opening stand of 233 runs to lay a strong foundation. Thereafter, the likes of Ollie Pope (108) and Harry Brook (101*) capitalised on the start with their partnership of 176 to put England in a commanding position.
The visitors smashed 174 in the morning session, picked up 158 post lunch despite losing three wickets in quick succession, and scored 174 again in the curtailed final session, where only 21 overs were possible as fading light forced early stumps.
All this action was possible only after an early-morning confirmation from the English camp that the tourists -- laid low by a viral infection in the lead-up to the beginning of the first Test -- had in fact recovered sufficiently to field an XI for an on-time start.
On their first day of return to Pakistan to play Test cricket after 17 years, England broke several records including the most runs scored on the first day of a Test match. A look at the few records that went for a toss on day one in Rawalpindi:
Most runs on Day One of a Test match
England's 506 runs, which came off a mere 75 overs with a stunning run rate of 6.75, is an all-time record for the most runs scored on day one of a Test match. They beat the 494 runs made by Australia against South Africa in Sydney in the first Test of the series in 1910.
Then, Australia finished on 494/6. Australia also made 482/5 in 86.5 overs in Adelaide against South Africa on Day One of the 2012 Test, a scoring rate of 5.57.
Four centurions on day one
Openers Zak Crawley and Ben Duckett aside, Harry Brook and Ollie Pope too completed hundreds, all but one of them getting to the three-figure mark at a strike rate of more than 100. This is the first time that there have been four centurions on day one of a Test match.
Record-breaking opening stand
Zak Crawley and Ben Duckett smashed an opening stand of 233 in 35.4 overs, a scoring rate of 6.53, making it the highest run rate in an opening partnership of 200 or more runs in Test cricket.
Overall, there have only been three double-century opening partnerships scored at in excess of six runs per over: Joe Burns and David Warner (6.29 runs per over v New Zealand in 2015) and Graeme Smith and AB de Villiers (6.22 runs per over v Zimbabwe in 2005).
Six fours in an over
England's Harry Brook smashed six fours in an over off debutant Saud Shakeel, making it just the fifth instance of a batter hitting six fours in one over of a Test match.
Sandeep Patil v Bob Willis in 1982, Chris Gayle v Matthew Hoggard in 2004, Ramnaresh Sarwan v Munaf Patel in 2006 and Sanath Jayasuriya vs James Anderson in 2007 were the other instances.
Brief scores: England 506/4 in 75 overs (Zak Crawley 122, Ollie Pope 108, Ben Duckett 107, Harry Brook 101 not out; Zahid Mahmood 2-160) vs Pakistan