Leinster will have to take the tough route if they want to add a fifth star to their blue jersey.
The four-time champions have been drawn against former champions Toulon in the quarter-finals of the competition.
If they beat Toulon, they will then travel to either Lyon or the defending champions Exeter Chiefs in the semi-finals.
Munster meanwhile has been drawn against French giants Toulouse and should they win that one they will play the winners of Wasps and Clermont Auvergne.
Both Leinster and Munster have home advantage for their games which take place on the weekend of April 2nd, 3rd and 4th.
Challenge Cup
Connacht has to travel for their quarter-final to take on Leicester Tigers while Ulster travels to Harlequins.
Should Ulster win they’ll take on either Dragons or Northampton Saints while Connacht will welcome either Ospreys or Northampton should they win their game.
Challenge Cup last-16 draw
Dragons v Northampton Saints
Ospreys v Newcastle Falcons
London Irish v Cardiff Blues
Harlequins v Ulster
Benetton v Agen
Zebre v Bath
Leicester Tigers v Connacht
Montpellier v Glasgow