Introduction: Jatizso and Neitiznot, also known as the Fremennik Isles, are the two Islands in the Lunar Sea that lie west of Miscellania and Etceteria.
You can go to one of these islands by talking to Mord Gunnars (for Jatizso) or Maria Gunnars (for Neitiznot). You can move between islands through the ice troll islands. You must have finished the Fremennik Trials quest in order to get to one of these Islands.
There are no respawns on any of the islands.

1. Jatizso Docks
   
   These are the docks of Jatizso, from this point you can get back to Rellekka. To do this, talk to Mord Gunnar or right click him and select the "Ferry-Rellekka" option.
   
   
   
   
2. Fishing spots
   
   Around the docks and the coast are several fishing spots.
   You can: Big-net fish here, cagefish and harpoon (tunas, swordfishes, and sharks)
   This is not a bad fishing spot, since it's pretty close to a bank.
   
   
   
   
3. Bank
   
   This is the bank of Jatizso.
   There's no difference to other banks, except that this one is smaller in size. This bank has no bank deposit box.
   
   
   
   
4. General store
   
   The minimap says general store, but it actually isn't one.
   These stores are rather food stores. The stores only sell food and you can't sell them anything they don't have in stock.
   
   
   
   Trade Keepa Kettilon to buy cooked food from him, what he sells (and which price) is shown in the image above.
   Trade Flosi Dalksson to buy raw food from him, what he sells (and which price) is shown in the image above.
   
   
5. Weapon store
   
   The weapon store sells several Mithril weapons. Which weapons and which price is shown in the image below.
   Also, this shop has some anvils which can be used to smith on. This spot is not very far from bank. Though there are closer ones.
   
   
   
   
6. Armour and ore store
   
   In this building you can buy all sorts of mithril armour and all ores up to adamantite, prices are shown in the image below.
   
   
   
   
7. Jatizso mines
   
   The entrance to the mines is located north-east of the western entrance to Jatizso. The mine has all ores up to adamantite in it, with an exception of copper. You can get copper ores in a small mine above the islands (see step 15).
   Remember to Watch out for ice trolls!
   
   
   
   
8. Neitiznot docks
   
   These are the docks of Neitiznot. From this point you can get back to Rellekka.
   To do this, talk to Maria Gunnar or right click her and select the "Ferry-Rellekka" option.
   
   
   
   
9. Yak field
   
   This field is full of, you've already guessed it... Yaks!
   Yaks are level 22 and have 50hp.
   Yaks drop: bones, raw yak meat, hair, and yak-hide.
   The hair can be turned into a rope on a spinning wheel. You can make some armour from the yak-hide with a needle and thread, after curing it.
   
   
   
   
10. Neitiznot bank and general store
    
    Neitiznot has a bank as well. Though it has bank chests and not bank booths.
    This bank has no bank deposit box either.
    
    
    
    In the bank is also a "general" store.
    However, it does not accept any items it doesn't have in stock already, just like the one in Jatizso.
    At the back of the bank you will find Slug Hemligssen, this NPC only has a use during the Fremennik Isles quest.
    
    
    
    
11. The Burgher
    
    In this building you will find two useful NPC's.
    If you lost your helm of Neitiznot you can buy one back from the Burgher (for 50K cash).
    Secondly you can cure your Yak-hide here, to do this right mouse Thakkrad Sigmundson in the south-west corner and click "Craft-goods". The costs are 5gp each and you can't tan any other hides here.
    
    
    
    
12. Large Geyser
    
    This is the Geyser.
    You can get some water from this geyser by using a bucket on it.
    
    
    
    
13. Woodcutting stump, clay furnace, and range
    
    This location has three useful things:
    The woodcutting stump is used to make a wooden Fremennik shield or a split pine (you need these for the Fremennik Isles quest.) These two items are made from Artic Pines which can be found around the island.
    The furnace is used to smelt ores in or to make Jewelery, it might be different by it's look but it functions the same as a standard furnace. Also this furnace is very close to the bank!
    The range is used to cook food on, it works the same as a regular range. This range is pretty close to the bank.
    
    
    
    
14. Spinning wheel
    
    A spinning wheel. You can spin items such as flax, wool, and hair here.
    This is the closest spinning wheel to a bank in RuneScape.
    
    
    
    
15. Copper mines
    
    The Fremennik isles have two copper mines. One north of Jatizso and one north of Neitiznot. Both of them have 3 copper rocks.
    It's not recommend using these since they're pretty far away from bank and the western mine has a troll lurking around and the eastern mine is overcrowded with trolls (And copper is not good at all, so why care?).
    
    
    
    
16. Coal and Runite mine
    
    This mine has 7 coal and one runite rock.
    Runite rocks are rare, which makes this mine a good mine. However, this spot is pretty close to a bank and a safe spot (no wilderness) so it's usually taken.
    The wilderness is still the best option to get runite ores. However, the risk of dying there is way higher.
    
    
    
    
17. Ice Troll dungeon
    
    These are the entrances to the Ice Troll dungeon.
    This cave must be accessed during the Fremennik Isles quest.
    To enter the cave during the quest you must enter through the eastern entrance. After the quest you must use the one on the west in order to enter the cave.