Now, while many games these days don't have the level-based formula, there are still many games of the past and present to discuss!! What are your favourite video game levels? I have a few to list off myself:

Strider 2's opening level is dear to my heart. I loved the game, and thus played through it multiple times. As such, the song and level are burned into my memory:

Ninja Gaiden's Chaper 3: I remember playing this level with my friends, and I thoroughly enjoyed it!! We died many times, but it was fun with 4 people taking turns before we finally persevered and beat the level.

Jun's stage in Tekken 2 is one of my favourites. I just love the music, and the green fields give off such a beautiful, happy vibe.

Those are some that came to mind for me!! What about you guys??

Some notable levels/areas for me:

Metroid Prime - Phazon Mines

Paper Mario: The Thousand Year Door - Glitzville (Chapter 3)

Dark Souls - Anor Londo

Metro Last Light - Ending

Last of Us - Winter

Persona 5 - Pyramid of Wrath

Sonic Mania - Metropolis Zone

Super Mario Odyssey - Metro Kingdom/New Donk City

Hmm too many levels to list here. but one in particular was that level in Super Mario Bros. where the mushrooms were colored orange? First time I got there, I spent quite some time jumping around before leaving the stage XD. I was in such awe lol.

The second level of Spear of Destiny (the sequel to Wolfenstein 3D) is great. I like it how the level basically has a big hub, with lots of small areas connected to it.

The first level in the first Call of Duty is pretty great. Actually all of the levels until (and including) the first town are pretty memorable. Talking about memorable, Stalingrad is also quite memorable in the game (and extremely annoying if you're playing on the hardest difficulty).

I love the levels set on the Great Wall of China in Crash Bandicoot 3.

Dynasty Warriors games, especially the older ones, have some great level design. I can't remember any specifically though because it's been a long time since I played the older titles. Also, level design in the series has gone downhill for a long time now.

Good question, I will try to come up with an answer soon.

Half-Life- Surface Tension:
This level was the original Half-Life at its best with clever design and set pieces throughout.

Half-Life 2- Ravenholm, Highway 17 and Anti-Citizen One:
The great thing about Half-Life 2 was that each chapter felt quite unique but still fit perfectly in the grand scheme of the game. Ravenholm's traps are brilliantly conceived whilst the atmosphere was more in line with a horror game. Highway 17 had some great moment with the buggy, gunship battles and the amazing segment on the bridge whilst Anti-Citizen One really makes you feel like a freedom fighter.

Deus Ex- Hong Kong:
Not really a level, more of a hub area that just had so much to do and so many different ways to achieve your goals.

Super Mario World-
Vanialla Dome 1: This just brings back so many memories. It's not even a particularly hard or specially designed level, it just brings back a lot of childhood memories. I also remember being amazed when we figured out the alternate exit.

Medal of Honour: Allied Assault-
Omaha beach: Technology has moved on a lot since then but at the time it was absolutely incredible.

Call of Duty 4- All Ghillied Up:
Not really known for its single player anymore but this was one of the most incredible pieces of scripted level design ever made.

Uncharted 2- Desperate Times and The Train:
This was Uncharted at its insane best. The collapsing building whilst in the middle of an intense battle and the sheer insanity of the train segment a couple of levels later.

Tomb Raider- The Lost Valley:
The very original Tomb Raider was enjoyable but fairly normal up until this point. The hidden T-Rex and velociraptors just upped the ante and was a pleasant shock to the system.

I absolute loved the Ancient Cistern in Zelda: Skyward Sword. Absolutely gorgeous dungeon with probably the most interesting background theme in the series. Loved the heaven/hell motif...way more clever than the typical fire/water/forest dungeon.

Metroid Prime - Phendrana Drifts.

I was about to write a whole rant about how good Halo 3's best levels actually where, then I realized no one cares. So i'll just list my favorite gaming levels off the top of my head:

Halo 3 - The Covenant>The Ark>Tsavo Highway>Sierra 117

Halo Reach - New Alexandria>The Package>Exodus>Oni: Sword Base

Banjo Kazooie - Freezezy Peak>Treasure Trove Cove>Bubblegoop Swamp> Gobi's Valley

Dark Souls - Dark Root Garden > Sen's Fortress > Undead Burg general area > Blight Town

DOOM(1993) - That one level where the level is like this Diamond shape with lava on all corners and there's the secret wall with a Centaur behind it

Sonic Mania - Greenhill Zone > Press Garden Zone > Studiopolis Zone

Mario Odyssey(as of now) - Wooded Kingdom, Bowser's Kingdom

Metroid Prime - Phenandra Drifts > Sunken Frigate > Phazon Mines > The Desert Level that goes into the Ruins with the Venus Fly Trap .... LOL I suck 

And that's all I can think of : (

Niven from Unreal Tournament.
Night Stalker from SOCOM.
Desert Glory from SOCOM.
President's Run from Driver.
Into the Abyss from Titanfall 2.
Effect and Cause from Titanfall 2.