Follow the road and right around the corner you will face a new type of enemy. It may not seem particularly impressive at first, but as soon as you get closer, it transforms. The new form is much faster and can deliver fatal blows. You should take advantage of the fact that the conversion takes 2-3 seconds. If you ran up to a creature and attacked it immediately, it is quite possible that you will kill the monster before it has time to transform.
Kill the first creature and turn left. There is a Confession Stone not far from another monster. Then go to the center, where there is a broken cart (next to it is the Soul of an Unknown Traveler).
You will face several enemies on the left side, one of which is a shaman. His special attack allows him to summon two creatures that will immediately start transforming. Thus, before you get closer, kill two of these monsters in the middle. The other two will pop out a little later. When this happens, jump from the shaman and fight the remaining two creatures. When you have killed the last of them, go to the stone gate.
You will face one enemy (the entrance is behind the gate, on the left). Kill the creature, collect the titanite shard and go left, where the road turns off. You will face a female enemy.
If you are caught in a series of hits, you will take huge damage. Dodge them, but maneuver left and right, because when you move in the opposite direction, she can still hit you. Use estus whenever a creature moves away from you, and strike when it finishes its own attack. Try to get behind her and perform powerful blows. Kill the creature and get the butcher's knife, and as you explore the path she came from, you will find the robber's ax, the robber's set, and the robber's twin daggers. Go to the gate, to the big bridge.
Pay attention to the number of enemies that are here. If there are too many of them for you, you should quickly leave this place and go halfway to the bonfire near the fortress, not far from here. On the other hand, if you want to kill them, remember that you need to lure single enemies from the bridge to the gate. This should make the fight easier. You can also try to push them into the abyss, but try not to fall yourself. After the battle, take Ember, who is next to the shaman.
Pay attention to the cave that is under the bridge. On the left, (when the bridge is behind you), you can find a safe descent (you will only receive minor damage). The path will turn towards the bridge and lead you to the cave. Watch out for the dogs and stay away from the edge (you don't want to be thrown down, do you?). You will find Morne's Ring and the Braille Divine Tome of Carim, which you can give Irina at the Purifying Chapel (That is, if you unlocked her in the Undead Settlement).
After you collect the volume, go up and jump down in front of the gate, on the bridge. Go below to get to the bonfire. You will face two knights: Henri and Horace. Speak with them and gain access to the Covenant: Blueguards.
The path that leads to the marshes is not easy. You will encounter several enemies along the way (if you stick to the path. If you go straight, you can avoid this place and jump down twice on the rocky area where you will find the Soul of the Unknown Traveler) and a large group of enemies at the end of it. They have a large log that they will use for charging. This will give you plenty of time to maneuver and hit them from behind. Just keep in mind that this is an easier way to fight, so lure them away from each other, or try to kill them as quickly as possible.
Although the swamps are large and dangerous, you can find a lot of interesting things here. Take the location shown in the screenshot and you have several ways to explore the location.