Infamous for their unique and sometimes crazy-looking keys, the warded lock is among the simplest locking mechanism ever developed.
While these locks have been used for almost 2000 years, they provide poor security and can be easily bypassed through the use of skeleton keys or impressioning.
In this guide, we will look into the history and development of the warded lock, how they work, and the insane vulnerabilities that eventually led to their downfall.
Let's get to it!
What is a Warded Lock
While the history of the lock and key is still unclear, it is believed that the Romans invented what is considered the first true obstacle in locks called "warding."
The idea behind warding is to create a specific design—or "pattern" —in the lock's keyway that creates obstructions that only a key with that corresponding pattern can pass.
A simple way to imagine warding is to think of a child's shape sorting toy—as seen below. The holes in these toys are designed with shapes (warding) that only allow corresponding shaped blocks to pass. You can only put the star-shaped block in the star-shaped hole and the circle-shaped block in the circle-shaped hole.
Warding is an obstruction that only allows the passing of predetermined designs.
Early implementations of warding in locks were quite simple and gave way to the device that we know of as the warded lock.
A warded lock is a security device that solely relies on internal obstructions ("warding") to block the rotation of the key. These obstructions can come in an almost endless variety of designs—as we'll see in a moment. To unlock a warded lock, you need a key that matches the exact shape and size of the warding.
For example, if a lock's warding was heart-shaped, you will need a key with a heart-shaped bitting to rotate through the warding and disengage the bolt.
A heart-shaped key may sound ridiculous, but it's nothing compared to the insane designs used in warded locks throughout the following centuries.
Craftsmen and locksmiths took it upon themselves to create the most intricate and artful warding that they could possibly conceive. Some designs were so complex that it literally felt like you were looking at a maze.
But regardless of how refined these locks became, they were plagued by two massive vulnerabilities—skeleton keys and impressioning. To anyone who understood these vulnerabilities, bypassing these locks—no matter how complex the warding—was as easy as eating a cookie. We'll discuss these weaknesses a little later in this guide.
Additionally, dishonest manufacturers could sell locks with intricate-looking keys, which would make the buyer assume the internal warding was just as complex. However, these bogus locks could only have a few true wards inside, giving them little security, and unless you opened the lock to check if the warding was actually there, you would have no idea.
These fatal flaws eventually inspired innovation, and in the late eighteenth century, the lever lock (tumbler lock) was designed and dethroned the feeble warded lock forever.
While the warded lock is still commonly found in low security, like vintage cabinets, the concept of using wards to obstruct the path of the key is found in nearly every modern-day lock.
How a Warded Lock Works
While the warded lock can be found in a near-endless variety of designs, the concept behind how they work is quite simple.
Let's look at a straightforward and popular design of the warded lock called the "wheel ward." This type of lock uses a series of circular wards ("obstructions") attached to a backplate and are placed in the pathway of the key.
If a key is used with the correct shape and sized cuts ("bitting"), it will pass the wards and disengage the bolt.
To illustrate this, check out the warded lock animation below!
On warded keys, the last protrusion on the key turns the bolt while the other key wards (the cuts on the key) pass through the wards.
However, if the key does not have the correct cuts, it will smash up against the ward and restrict the key from rotating further—as illustrated below.
The models above are examples of the most simple variation of the warded lock. However, designs could get quite intense, including placing wards on the front and backplates.
Some locks would even include a barrel that allowed them to put wards on all three sides of the keyway.
But even when warded locks have insanely-complex designs, the concept behind how they work remains simple.
An additional note, you may have noticed in the animated diagrams above that the key directly engages and retracts the locking bolt. This is common for most warded locks.
Warded Lock Keys
Warded lock keys are notorious for their vintage look, stout metal frames, and unique bitting.
They are often referred to as "skeleton keys," however, this is inaccurate.
Warded lock keys are not skeleton keys. Instead, skeleton keys are a type of key that has been modified to open multiple warded locks. They are called skeleton keys because they are keys that have been "cut down to the bone" or the bare essentials needed to work.
You can think of skeleton keys like lock picks or tryout keys for warded locks. Skeleton keys are an incredible type of lock picking tool that we'll discuss in a moment.
Warded lock keys are simple creatures and have four primary parts.
The bow is the large section of the key that grants the leverage required to rotate the key. It is also the decorative part of the key.
The bit is the section that protrudes from the end of the key and is used to engage and retract the locking bolt.
The long section of the key which links the bow and the bit.
The Key Wards
The key wards are cuts made into the key's bit that match the internal warding of the lock. If the key wards do not match the lock's warding, the key will not work. They can also be referred to as the "bitting" or "cuts."
With that little tidbit out of the way, let's jump into the vulnerabilities of the warded lock and why they are rarely used today!
Warded Lock Vulnerabilities
While warded locks reigned supreme for hundreds of years, using them provided a mere speckle of security. While most locks—including the modern pin tumbler—are rather easy to exploit, warded locks are plagued with some of the most ridiculous vulnerabilities and are among the easiest to bypass.
Two of the most well-known and severe weaknesses of the warded lock are skeleton keys and impressioning.
Let's jump into each of these vulnerabilities and why they ruin the security of this lock.
The first and most popular bypass is the use of skeleton keys.
As we covered earlier in this guide, the term "skeleton key "is often used to describe 'all warded lock keys' or even' master keys.' This is inaccurate.
A skeleton key is a key that has been cut down to its “bare bones”, leaving just the bit needed to turn the bolt—as illustrated in the image above!
By cutting away the unnecessary bitting of the key, there is no longer anything left to smack against the wards in the lock—allowing you to bypass the warding completely.
For clarity, check out the animation below!
Using a skeleton key is as easy as using the correct key! Pretty ridiculous, right?
Now there is a drawback to using skeleton keys. Because warded locks are designed in various shapes and sizes, a single skeleton key cannot open all warded locks.
Rather, low-lives of the day would carry a collection of popular skeleton keys, allowing them to try different shaped keys. These collections are also known as tryout keys!
Vintage skeleton keys are relatively hard to come by but easy to make yourself.
However, for modern warded locks, you can cheaply buy a set of tryout keys that work for most locks—such as Peterson's Set of 5 Warded Lock Picks.
Skeleton keys are an awesome topic and if you would like to dive a little deeper, consider checking out my full writeup here (coming soon)!
Along with the plight of skeleton keys, warded locks can also be easily impressioned.
Impressioning is the act of making a new key for a lock, without duplicating an existing key or disassembling the lock to look at the internal components.
This may sound like a complicated task—after all, how easy could it be to make a new key without being able to see the internals of the lock?
While impressioning most types of locks can be a tedious task, warded locks are relatively simple.
Because the wards are fixed within the lock and do not move, all we need for a new key is the location, size, and shape of the wards!
They can easily be found by coating a key blank (or any item you wish to use as a key) with any material that can be easily scratched off—such as wax, paint, or even a Sharpie marker.
The key blank is then inserted into the keyway and rotated (as if trying to use the key). The blank will slam up against the warding and scuff the coating—making an "impression" of the wards on the key.
This impression will give you a good idea of where the internal obstacles (wards) are and where to make the cuts on the key.
Within a short period of time, you can cut a working key without any access to the original. This makes the warded lock fairly worthless against anyone with access to metal and wax!
While the direction of lock-based technology is racing towards digital, warded locks will forever be remembered as the lock that truly started it all and paved the path for innovation.
I hope that you enjoyed this little guide and that it helped you better understand and appreciate the warded lock.
But it doesn't stop here! If you would like to learn more about locks, lock picking, and security, be sure to drop by my academy for more free guides.
Thanks for reading!