Andrew Petersen is Professor and Director of Research in Islamic Archaeology at the University of Wales Trinity Saint David. He is currently directing excavations at the eighteenth-century site of Ruwayda in northern Qatar. He has published many articles and several books on Islamic archaeology, including Bones of Contention: Muslim Shrines In Palestine (2018), The Medieval and Ottoman Hajj Route in Jordan; an Archaeological and Historical Study (2012), The Archaeology of Towns in Muslim Palestine (2005), Gazetteer of Medieval and Ottoman Buildings in Muslim Palestine (2001) and A Dictionary of Islamic Architecture (1998). ; Denys Pringle is Emeritus Professor in the School of History, Archaeology and Religion at Cardiff University. In addition to his four-volume corpus, The Churches of the Crusader Kingdom of Jerusalem (1993–2009), his recent publications include a volume of translated texts, Pilgrimage to Jerusalem and the Holy Land, 1187–1291 (2012), and a volume of collected studies, Churches, Castles and Landscape in the Frankish East (2013). His detailed historical and archaeological study of the town walls of Byzantine, early Islamic and Crusader Ascalon has recently appeared in Ashkelon 8 (2019).