Ulster will get the 2017/18 Champions Cup up and running when they host Wasps on 13 October after the ERC revealed dates and times for the first four rounds of the competition.
Kingspan Ravenhill will see the first action of the new campaign when the Aviva Premiership side travel for the Friday night fixture.
The following day (1pm) Leinster host Montpellier at the RDS Arena, while Rassie Erasmus’ side travel to France for their opening fixture on Sunday 15 October.
The Stade Pierre Antoine is the venue where Castres will look to make the early running in Pool 4 (KO 1pm Irish time).
Saracens will launch their bid for a third successive Champions Cup title by facing Premiership rivals Northampton Saints at Franklin's Gardens.
Mark McCall's side have claimed back-to-back European titles, and could emulate Toulon by claiming three on the trot this term.
Round Two will see Ronan O’Gara return to Thomond Park again as Racing 92 make a Saturday visit (5.30pm), with Leinster travelling travelling to Scotstoun earlier on 21 October (1pm).
The back-to-back Christmas fixtures have thrown up some interesting pairings. Munster host rivals Leicester on 9 December (7.45pm) before making the trip to Welford Road eight days later (5.30pm).
Ulster take on Harlequins at the Stoop on 10 December (1pm) before a six-day turnaround sees the 2012 Premiership champions arrive at Kingspan Ravenhill the following Friday (7.45pm).
The final fixture in Round Three will be a Sunday fixture at Sandy Park where Exeter Chiefs entertain Leinster (5.30pm), before the English champions travel to the Aviva Stadium the following Saturday (3.15pm).
The dates, kick-off times and TV coverage for the Round 5 and 6 fixtures in both tournaments will be announced in December following the completion of the Round 4 matches.
