How has locking our doors changed over time?


They keep our families, businesses, and possessions safe every day, but when was the last time you stopped to appreciate how door locks have evolved over time?

In this blog, we delve into the fascinating history of an invention which, though many take for granted, provides enormous value to many people around the world. By looking at early examples and the milestone mechanisms they inspired, we put into context the true importance of modern access control solutions like Codelocks’ KL1000 G3 NetCode®.

Wooden locks and wards

The first locks were made using wood as far back as 4,000 BC. The earliest known tangible example – estimated to be around 2,700 years old – was recovered from the ruins of an Egyptian palace.

Remarkably, these early locks used pin tumbler mechanisms not dissimilar to many of the modern keyed locks we see today, where small pins inside the device are lifted by a key to allow opening. These primitive versions are often referred to as ‘Egyptian (or Egypt) locks’ due to their widespread use in the area, although historians believe the technology first appeared in the historical region of Mesopotamia in Western Asia.

The effective pin tumbler mechanism provided inspiration for the Romans, who replaced wood with iron and bronze, to build more robust versions, before adding springs to their locks’ pins for increased reliability.

The Romans also went a step further and changed the look of keys forever by introducing wards:  those projections around a lock’s keyhole that allow only a key with corresponding design to turn inside. This paved the way for another pivotal Roman invention: the padlock.


The padlock is thought to have been invented independently in both the Roman Empire and China!


Warded locks remained the industry standard long after the fall of the Roman Empire. Their popularity grew internationally and, rather than invent alternatives, locksmiths worldwide focused for centuries on making warded locks as secure as possible with increasingly elaborate key and mechanism designs. Over time, keys for warded locks – known as ‘skeleton keys’ due to their appearance – became pieces of art as much as security tools.

A modern era of locks begins

Things were then relatively quiet for thousands of years in the locksmith industry, until a wave of innovation hit in the 18th and 19th centuries, with England at its center.

Robert Barron invented the lever tumbler lock in the late 1700s, which uses a series of levers to prevent an internal bolt from moving. The Chubb brothers then improved on Barron’s design in the early 1800s by adding springs and additional levers for more protection against picking. Even now, many home insurance companies require policyholders to use five-lever locks on external doors to make their cover valid.

Around the same time, English inventor Joseph Bramah patented a cylindrical ‘safety lock’, based loosely on the early pin tumbler mechanisms from Ancient Egypt. Again, this design was quickly developed by other locksmiths, most notably American Linus Yale Jr, who in the 1840s paired the technology with a modern flat key design that was easier to produce and replicate, making it more suitable for mass production.

These breakthroughs set standards for home and workplace security that would last for hundreds of years.


Joseph Bramah’s Ancient Egypt-inspired ‘Challenge Lock’ remained unpicked for 67 years, despite Bramah publicly encouraging attempts!



The locks of today and tomorrow

The technology developed in the 17-and-1800s can be seen in most modern key-operated locks but that’s not to say evolution has halted. Keyless access solutions are the next stage in the evolution of the lock, replacing old fashioned keys with numerical codes for greater security and convenience.

Over the last 30 years, coded locks themselves have evolved, and the current range available can cater for all access control needs of both home and business owners. Codelocks’ access control range includes simple mechanical coded locks that are robust, affordable and easy to install in internal and external environments, and electronic coded locks that provide more functionality, including the ability to connect to external alarm systems. Smart locks, such as the CL4510 offer even more functionality – including the ability to generate and send single-use, time-specific codes from your smartphone or laptop.

The latest addition to the family, is the KL1000 G3 NetCode lock – designed specifically for lockers and cabinets. It comes with all the popular features of the KL1000 Classic Plus, including Private and Public Functions, a 24hr auto-unlock countdown timer in Public Function and up to 20 User Codes in Private Function. Equipped with Codelocks’ NetCode Technology, single-use time and date sensitive codes can be sent to users via email or SMS, giving them temporary access until the code expires.

The KL1000 G3 NetCode is perfect for locations where cabinets and lockers may be allocated on both short- and long-term basis, and it doesn’t need WiFi to operate. It’s designed to meet the needs of many businesses that require flexible locker solutions, most recently to accommodate the move to hybrid working. The API can be easily integrated into any system, giving hybrid workers convenient access to a secure locker via their email or SMS.


Ready to find out more about how the latest keyless locks can simplify your life?

Get in touch





The Codelocks Control + Convenience logo and NetCode® are registered trademarks of Codelocks Ltd., registered in the United Kingdom, United States and other countries and regions.


14, Jul 2022

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