Old Sarum and the landscape around it, is the subject of a research project  undertaken by the Archaeology Department at Southampton University, that began in the spring of 2014. Every year since then, a team made up of third-year undergraduates accompanied by University Staff, has spent several weeks at Old Sarum as part of the training programme.
Before the project team came to the site, LiDAR  image data made available free of charge by the Environment Agency was carefully studied. Plans were drawn up to focus on promising 'points of interest' shown in the images, in order to use surveying time in the most efficient way.
In autumn 2014, news was released to press agencies to announce what early results from the scanning techniques had uncovered.
Image reproduced here with the permission of the Environment Agency and University of Southampton
"Experts have produced a detailed plan of Old Sarum without any digging at the site. The latest scanning techniques have uncovered a network of buildings at the 11th century hillfort, once a thriving medieval city.
Residential areas have been identified and there is evidence of industrial features such as kilns or furnaces.
The university's director of archeological prospection services Kristian Strutt said 'Archaeologists and historians have known for centuries that there was a medieval city at Old sarum but until now there has been no proper plan within the city walls. Our research so far has shown how the entire outer bailey of the monument was heavily built-up in the middles ages, representing a substanial urban centre.'" 
Since that 2014 announcment, residents of Stratford sub Castle have been keen to learn more about what has been discovered so close to our village. The 'Friends of St Lawrence Church' arranged for expert speakers to come to packed venues in March 2015 and again in May 2017, so that further research findings and their historical context could be explained.
In 2016, the University of Southampton encouraged local residents and archaeological groups to participate in the OSLP and a study day was held at the University in January 2017 for any interested parties. When in early April 2017 the students extended their investigations to include the fields between Old Sarum and Stratford sub Castle, several local volunteers were able to take an active part in the surveying. Our website's Photo Gallery includes images and descriptions of their 2017 geophysical activities. Up to this point, all of the work had been non-intrusive to the landscape.
Students will return to Stratford sub Castle for a Field School planned for July 2017. The programme will include geophysical surveying, field walking and excavation.
 Light detection and ranging - Wikipedia explanation
 Source - The Journal December 11, 2014