The three crosses represent Christ and the two bad guys that were crucified with him. The good bad guy was on Christ right side. The little curl down on the bottom of the smaller right cross means there is a treasure in a hole, or cave, depending on how close to a cliff you may be. Since this cross is on the right it probably means there is a treasure, straight to the right, on the right side of the big cross.
I don't think your left, two blue markers mean anything. I believe the third one means dig down on the right. If you had a picture of the area around this marker I could be more precise in my comments. You have a lot of triangles which could be meaningful, but you don't have a picture of the area. I believe this is really one of those reversal markers. What looks like it should be on the left is really on the right. Now if this is laying flat and is not on a rock wall, the treasure could be on the upper right side is the location for a dig.
You might look for a lone boulder that looks out of place, or something that that comes in threes, like three boulders or three trees. If you see something like that with a lone boulder or tree standing alone, you might look there.
