However below the water lurks several level 10 Drowners, and you can't use your swords in the water. You can spot the place by looking for a broken boat still floating on the water. This one in particular is just East of the Nilfgaardian Garrison, in the middle of a large part of the river. The map marker may say Spoils of War, but it's really just more guarded treasure. You can also find Witcher Gear here that will unlock the Side Quest: Scavenger Hunt: Viper School Gear. Enter the crypt and defeat him, then cast enough light to find the various treasure chests located within. Getting him to half health will cause him to retreat - whereupon you must follow him by blasting down the door with the Aard Sign. There will likely be a level 7 Wraith guarding the Place of Power out front. Travel North from White Orchard across the river and enter the cemetery. This guarded treasure may look like it is behind the White Orchard Graveyard, when in fact it is beneath the ground in the crypt.