In 2009 Henderson began a project, in collaboration with the Hellenic Ministry of Culture, to examine Pavlopetri, a submerged Bronze Age town located off the coast of Laconia in Greece. 

One of the primary objectives of the project has been to record the submerged town in as much detail and as accurately as possible, in the process building and field testing a range of new technologies. This has had the dual function of achieving complete preservation by record of the fragile remains of the site through a range of formats whilst at the same time promoting the development of new methods of underwater archaeological survey.

The commercial impact on NMGI has been significant and is on-going. As a result NMGI and have invested future time and resources in developmental research with The University of Nottingham. As well as donating equipment to the University, staff from NGMI have accompanied Henderson on recent projects in Scotland (including scanning a submerged Viking harbour in Skye in 2012 which was filmed as part of a BBC 2 documentary The Last Battle of the Vikings) and in Italy in 2013 recording the remains of the Battle of the Egadi Islands off the coast of western Sicily.

Nautilus Marine Group International (NMGI), a North American offshore engineering company associated with Kongsberg Mesotech, joined the project to field test cutting edge sonar technology and assess its effectiveness for producing accurate geometric surveys of submerged features.

Pavlopetri offers a unique opportunity to test the accuracy of marine survey equipment for non-academic organisations as it sits in shallow water (less than four metres), has clear structural remains across a seabed area of 8ha and, most crucially, has been surveyed using a Total Station in millimetre accuracy – this survey data provides a baseline template against which the results from all the other digital technologies used on the site can be accurately tested.

The collaboration was pump-primed in 2009 by a University of Nottingham Knowledge Transfer grant with NGMI returning in 2010 and 2011 using their own funds to further develop the scanner and field-test a range of other technologies such as swath bathymetry, side-scan sonar, echo-sounding and sub-bottom profiling. The collaboration has delivered significant commercial and innovation benefits to NMGI, allowing them to develop refinements to their tool and to identify a new market for their scanner. They have subsequently carried out commercial work using the refined tool including contracts in the archaeological commercial sector.

This project represents a ground-breaking achievement in terms of underwater scanning through significant improvements to the speed and in particular the accuracy with which underwater sites can be surveyed. Combining this with improved visualisation processes (through a further partnership with Australian Centre for Field Robotics at the University of Sydney), the project has changed the way archaeologists and the public visualise, interpret and understand marine cultural heritage, contributing to local and national-level policy changes in terms of the protection and preservation of submerged sites in Greece. Also the imagery produced was fundamental in obtaining a commission for a major BBC/Discovery documentary on Pavlopetri which has been shown worldwide to over 15 million people.