diff --git a/src/main/java/electroblob/wizardry/block/BlockTransportationStone.java b/src/main/java/electroblob/wizardry/block/BlockTransportationStone.java
index ea0595a1..979fa0f4 100644
--- a/src/main/java/electroblob/wizardry/block/BlockTransportationStone.java
+++ b/src/main/java/electroblob/wizardry/block/BlockTransportationStone.java
@@ -73,7 +73,7 @@ public class BlockTransportationStone extends Block {
 	public boolean isOpaqueCube(IBlockState state){
 		return false;
 	}
-	
+
 	@Override
 	public boolean isSideSolid(IBlockState base_state, IBlockAccess world, BlockPos pos, EnumFacing side){
 		return side == EnumFacing.DOWN;
@@ -147,7 +147,7 @@ public class BlockTransportationStone extends Block {
 								if(locations.isEmpty()) locations.add(here);
 								else{
 									locations.remove(here); // Prevents duplicates
-									locations.set(locations.size() - 1, here);
+									locations.set(Math.max(locations.size() - 1, 0), here);
 								}
 								if(!world.isRemote) player.sendStatusMessage(new TextComponentTranslation("tile." + Wizardry.MODID + ":transportation_stone.confirm", Spells.transportation.getNameForTranslationFormatted()), true);
 							}