Summary While archaeology is often considered to focus on the land that lies beneath our feet, significant amounts of material culture have been lost to us beneath water, whether in seas, lakes, rivers, or submerged caves. The world of underwater archaeology, however, is increasingly recognized as a field that is vital to our understanding of the past. The chapters gathered together into this volume draw on research first presented at the Fourth Warsaw Seminar on Underwater Archaeology, held at the University of Warsaw on 18-20 November 2021. From the seas of the Caribbean through to the Mediterranean and Norway, and from Antiquity through to contemporary times, the chapters presented here offer a dazzling array of different approaches to underwater archaeology and outline the potential that changing technology presents in this expanding field. TABLE OF CONTENTS List of Illustrations Preface Malgorzata Mileszczyk, Magdalena Nowakowska, Magdalena Krzemien, and Joanna Staniszewska Foreword Bartosz Kontny Professor Iwona Modrzewska-Pianetti Karolina Trusz Iwona Modrzewska-Pianetti: Selected Works Section I. The Mediterranean 1. The Water Landscape in Sicily and its Cults between Classical Sources and Archaeological Sites. Preliminary Analysis Giulia Raimondi 2. Punta Prima Project: In Situ Preservation of an Early Roman Shipwreck near Formentera Island (Spain). An Educational Experience Enrique Aragón, Malgorzata Mileszczyk, Javier Rodríguez, and Joanna Staniszewska Section II. The New World 3. Manantial de la Aleta - The Top of the Iceberg in a Caribbean Cave Przemyslaw Adrian Trzesniowski Section III. The Baltic Sea 4. Portu de Heliousound in Norwegia. Submarine Archaeological Investigations in the Late Medieval and Modern Era Outport of Ny-Hellesund, Southern Norway Elling Utvik Wammer Section IV. Rivers of Central Europe 5. Wreck Hunting in the Vistula River near Warsaw Artur Brzóska, Piotr Prejs, and Andrzej Szerszen 6. Live Acoustic Pictures from the Depths. Shipwreck SZD1 Survey with Adaptive Resolution Imaging Sonar (ARIS) Piotr Malinski and Pawel Mikolajewski 7. Between Hydrography and Underwater Ethnoarchaeology. Modelling of Selected Wrecks in the Lower Oder as Part of Research on the Geoclassification Method of Ferromagnetic Bottom Objects Izabela Bodus-Olkowska, Grzegorz Zaniewicz, and Piotr Malinski Section V. Lakes of Central Europe 8. Small Finds from the Great Water. Unexpected Discovery from Lake ?niardwy Agata Grzedzielska and Bartosz Kontny 9. Unique Medieval Iron Spearhead from Lubanowo Bartosz Kontny 10. Palaeoecological Studies of Lake Pilakno Micro-region, Mragowo Lakeland. Preliminary Results Malgorzata Mileszczyk, Magdalena Filoc, Miroslawa Kupryjanowicz, Dominika Kofel, and Magdalena Nowakowska 11. Diving Equipment Used in the 1960s Lake Pilakno Archaeological Research Malgorzata Mileszczyk and Karina Kowalska