Coincidentally, both of those milestones at Old Trafford came in Ashes Tests:

Shane Warne became the first player to the 600-wicket milestone in 2005, getting Marcus Trescothick out caught behind by Adam Gilchrist off a mis-timed sweep shot that took a juggling effort to complete during the 3rd Test of the 2005 Ashes:

Fast forward to 2023, and Stuart Broad became the 5th player to reach 600 Test wickets when Travis Head mis-hit a short ball to Joe Root, taking a low diving catch in the deep.

Which also means Broad took his 200th, 500th and 600th Test wickets at Old Trafford.

The other locations for 600th Test wickets:

Muttiah Muralitharan’s 600th Test wicket was Bangladesh’s wicketkeeper Khaled Mashud, caught by Lasith Malinga in the 2nd Innings of the 2nd Test at Bogra in 2006.

Indian great Anil Kumble’s 600th Test wicket was Andrew Symonds, caught off an MS Dhoni deflection by Rahul Dravid at the WACA in 2008, the match that ended Australia’s second 16-Test winning streak.

And James Anderson’s 600th Test wicket was Pakistan captain Azhar Ali caught in the slips by Joe Root at the Rose Bowl in Southampton in 2020:

There’s another coincidence – Joe Root caught Anderson and Broad’s 600th wicket.

And, this milestone also makes this English XI the first team in Test match history to contain 2 players with least 600 Test wickets.