I loved Siege of Orgrimar. It really had a lot of cool fights, we were actjally fighting in Orgrimar! Really loved it.
2nd would be Castle Nathria - oh it had such a good vibe, amd was completely foreshadowed by bad systems of SL.
3rd place has a lot of candidates, a lof of good raids, but probably Naxxramas. It’s very iconic indeed.
Some honorable mentions: Karazan, ICC, Nyalotha, ToT, …
Sashy left! 
Ulduar and Castle Nathria for me personally
Gonna have to go with Ulduar. I will never forget how it handled hard modes as well. It was better than anything before and anything since.
It was fun, it was big, it was full of lore, the bosses were great, and it looked awesome. It also had this amazing challenge for the select few called Zero Lights in the Dark. It spanned the range as a single instance and it was all about discovery. Almost anyone could play through it, but if you just kept digging around you found more and more and more difficult ways to beat it and get better loot and there was a little bit of story behind all of it.
However, I also tremendously enjoy The Thunder King (5.2) simply due to its trailer… does that count?
i forgot about all the amazing raids you guy lissted like karazhan is also iconic. now we have aberrrus and VOTI xd lul
Massive agree with this! Antorus was such an amazing experience and such an epic ending of an expansion.
This.
Not only were they mechanically interesting, but I was actually excited about smashing some mean orcs while at it.
Both the gameplay and story were fun and honestly I enjoyed the vibe. Good times…
I have to give honorable mention to Karazhan though. Although very simple mechanically, the atmosphere was fun and this raid stayed relevant until the end of the expansion.
Every new Expansion raid was technically years ahead of the previous. But it was always the last raid of each expansion that was the stand out raid of that expansion. Unfortunately Ulduar was eclipsed by ICC.
Objectively?
Ulduar. It was, and still is, the best raid of all time. So much so that 3.1 has no additional content other than the raid, and no one at the time cared because of how great Ulduar was.
Subjectively?
That’s a tough one. I’d say for me it’s Nathria because most of the bosses were great and the music was sublime. I had great memories of that raid, especially during S4 of Shadowlands.
With the exception of Highmaul - but then again first raid in each expansion was always the weakest. Gorefiend was pure evil to.
SoO was a high point for me, along with fond memories of the TBC raids (inc. kara! Was so fun with Shade on release)
Throne of Thunder was 10/10, then Karazhan because it’s a classic
Sunwell or firelands. Those raids i have best memorys of my old good friends.
Ulduar is peak wow
Where is Timewalking Ulduar blizz?
This, Ulduar (in its time) was by far the best raid that ever was created…
I doubt there will be ever a raid like this again
Ulduar. It had so much variety in encounters. And Hard modes that would unlock a special boss later on.
This exists for years now.
Ulduar without any doubts. The boss fights are original, the graphical design of the raid and its equipment that drops are breathtaking. All these years later tier 8 sets are still my number one favourite.
Karazhan for me. Coming from Vanilla Kara was amazing.
Antorus.
And I also liked Emerald Nightmare.
I really enjoyed tomb of sargeras