Spiders are notorious climbers. This is why people try to prevent them from climbing walls. However, they still find ways to get up. Here are some tips to keep them away.
To prevent Spiders from gaining access to a structure, place signs around it. The spiders will not be able to climb over the sign. Another tip is to build a fence. You can also use a Glowstone to cover the top of the fence.
There are other types of blocks that Spiders cannot climb. Cactus and Honey Block walls do not allow Spiders to climb. If the spiders gain access to a cactus wall, they will hurt themselves in the process of climbing.
Another way to prevent Spiders from climbing is to place an overhang on the wall. Overhangs are built as extensions to the walls. They are slippery and would prevent Spiders from gaining access.
Spiders can climb over glass, but they do not have the ability to walk through it. Most mobs are unable to see through glass.
A lava wall or ice wall is another block that Spiders do not have the ability to climb. These blocks are prone to melting and would burn the Spider.
If you can’t prevent Spiders from climbing, you can always try to make the area look safer. One good idea is to put lights inside the base to keep the area bright. When light levels drop, Spiders become hostile.
Whenever Spiders are trying to climb a wall, they will approach as close as they can to the player. This is how they are able to detect the player. It may take them a few attacks to realize that they have been hit. Once they are able to notice the player, they will continue to move blindly for a few seconds.