Over 100,000 hectares of land is now registered in South Lakeland, Cumbria.
It is regarded as an important milestone for the Land Registry, which is encouraging other landowners in the area to take advantage of a voluntary land registration scheme, which offers them more certainty and security about what they own.
The Cumbrian initiative is part of a drive by the Land Registry, the government department responsible for registering land ownership in England and Wales, to help landowners identify and register what they own.
More than 30% of England and Wales remains unregistered, while in South Lakeland the figure stands at 41%, representing more than 72,400 hectares.
In Cumbria as a whole more than 57.7% of land has now been registered, around 414,800 hectares in total.
Harry Charlton, register development manager for Cumbria, said: "We have a straightforward and cost-effective system for checking and registering who owns what and we're currently offering a 25% discount on the costs for those who voluntarily register their land."
State-backed registration gives landowners greater security of title, providing them with better protection against claims of adverse possession. Landowners also know the administration of their land holding is in good order with key information in one place and easy to access.