Cardiff and Bilbao have been selected as the host cities for the Investec Champions Cup and EPCR Challenge Cup finals in 2025 and 2026, respectively.
Next year's showpiece matches will take place at the 74,000-capacity Principality Stadium in the Welsh capital.
Athletic Bilbao's 53,000-seater San Mames stadium, which previously hosted the matches in 2018, will stage the two finals in 2026.
Cardiff Arms Park was the venue for the final of the inaugural European Rugby Champions Cup - then known as the Heineken Cup - in 1996 when Toulouse beat Cardiff 21-18.
European Professional Club Rugby chairman Dominic McKay said: "In returning to Cardiff, 30 years on from the iconic first final means a great to deal to us and our friends here in the city, and we will celebrate the milestone appropriately.
"We know this rugby heartland will not only be proud to host this historic weekend, but will welcome rugby fans from across the world to join us.
"For 2026, we cannot wait to return to Bilbao, which hosted a superb celebration of rugby in a world-class destination in 2018."
This season's Champions Cup final is set to take place at the Tottenham Hotspur Stadium in London on 25 May, with the Challenge Cup decider also taking place at the same venue the day before.
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