How to find Marguerit's Greenhouse - Subnautica: Below Zero

In this guide I'm going to explain how to find Marguerit Maida's Greenhouse in Subnautica: Below Zero. Starting from the Drop Pod (your main base at the start of the game), I'll be passing by the Delta Station island and then take a left to reach the iceberg where the Greenhouse is located. It is quite a lengthy travel, so a Seatruck is definitely recommended, but there aren't really dangerous creatures on the way, so it's pretty safe to go even with just a Seaglide and fins. I also recommend having fabricated the compass beforehand, which will make your exploration much easier, and bringing a beacon to signal the Greenhouse's location for future travels.

In order to find the greenhouse, you're going to start from near where your Drop Pod is located. After finding it, if you look back on the main icy land where you first landed you should locate a big icy slope reaching for the sky, and that's where the journey begins.

After locating the slope, you must face directly south if you have already fabricated the compass, or you can simply turn 180 degrees from the slope to pretty much look at your Drop Pod. Once you're ready, you can start heading straight in that direction.

I recommend traveling as close as possible to the surface in order to avoid encountering some annoying fauna, and also to make sure you recognize the landmarks on the way you need to keep an eye on to know you're going in the right direction: first, you'll encounter a large iceberg you can simply go around; then, a broken Alterra station with a black cable emitting sparks underwater, which you can avoid by hugging its right and continuing on.

Once you start encountering a lot of hot spires with black smoke coming out from them, you know you've almost reached the Delta Island, which is basically about 200 m in front of you. Just watch out for the Cryptosuchuses in the area: they don't deal a lot of damage, but they can be quite annoying if they start following you.

Once you reach the Island for the first time, the PDA should notify you of a beacon close to your position, the Delta Station Dock beacon, which will automatically appear on your screen along with the other signals. The dock is easy to spot both underwater and above because of the floaters and the big antenna in the background, and it's your halfway stop.

After finding Delta Station Island, to resume your travel you're going to start by turning left from the dock you've just reached and continue hugging the left side of the island; on the way you will pass through a small open tunnel which will take you to a little slope and a beach above it with some Pengwing and Penglings and lots of rock formations with the antenna visible behind them.

Near the beach, positioning yourself exactly like in the photo, looking directly at the antenna, you'll be in right spot to have the antenna pointing west (which you can verify with the compass). You then must turn 180 degrees to have the antenna behind your back to position yourself looking directly east (again, easier with the compass), and then you can begin heading straight in that direction. Marguerit's Greenhouse will be about a kilometer away.
While you're still not far away from the Island, the terrain beneath you will shift from black to golden rocks, but the depth will increase rapidly once you continue traveling so don't rely too much on that. What you must keep an eye on is the change in water colour, from blue to green, once you enter the Lilypad Islands biome - you'll know you're going in the right direction if you encounter some closed Lilypads on the way.

Additionally, on your left you should see some icy platforms, while on your right there should be large open Lilypads, grown to reach the surface.

Keep going straight until on the surface you encounter a large pointy iceberg with ice platforms on its left; hug the iceberg's left side and continue on.

Behind the iceberg you're passing by you'll spot other icebergs on the left and another large iceberg directly behind it on the right: that's the one you're looking for (in the photo it's the one with the beacon icon). You'll know it's the right one once you spot Alterra cargo boxes, various plants and bone remains on its surface.

You can get on top of the iceberg by reaching a little slope in front of the area where the Alterra boxes are; you should also be able to spot some Light Sticks on its surface and a cave entrance with ice stalactites on its right.

Inside the cave you'll find lots of Fevered Pepper Trees to help with the cold, a Light Stick and two tunnels, one that continues straight ahead and one on the right that goes up into the mountain. The tunnel on the right (near the Light Stick) is the one you must enter to continue; the tunnel in front of you leads to the water, in case you need another access.

Enter the tunnel on the right and follow it as it continues up and right; you'll encounter a slope which will take you to a small flat area and a bridge, over which you can spot the Greenhouse.

That's it. Congratulations on finding Marguerit's secret base!

The area where Marguerit's Greenhouse is located is full of useful materials and resources.
First of all, inside the Greenhouse you can find Chinese Potato Plants, Horseshoe Shrub Plants, Small and Large Marblemelons, and Preston's Plants (which spawn exclusively inside the Greenhouse, and can't be found anywhere else in the game): along with the Frost Vase Plants and Fevered Peppers you can find outside, these are useful plants to grow inside your base for an infinite food supply or to feed a bioreactor to generate power.
Secondly, the Greenhouse's iceberg and the ones around it can usually spawn with veins of useful minerals and metals, like titanium, copper, silver, and magnetite, but some could require a Laser Cutter to access the internal rooms, since most of the icebergs in this area are hollow inside. Also, one of the icebergs nearby has an Architect Artifact on its surface, which I'm pretty sure doesn't get a beacon signal like other Artifacts and makes it difficult to locate.

Hope this guide was useful!