Prior to the 1950s, general shore-protection practice was to use hard structures to protect against beach erosion or storm damage. Generally, the hard structures can be divided into two categories. The first category functions through anchoring the position of either a shoreline or a dune-line, such as seawalls and revetments. The second category is mainly sand-trapping structures such as groins and detached breakwaters. Realizing that the accumulation of sand produced by a structure is at the expense of an adjacent section of the shore, since the 1970s, 90% of the US Federal appropriation for shore protection has been for beach nourishment. Although beach and dune nourishment has become by far the most dominant approach to shore protection, principles of hard engineering structures are still reviewed in this chapter. More recently, since the 2010s, Engineering with Nature (EWN), defined as the intentional alignment of natural and engineering processes to efficiently and sustainably deliver economic, environmental, and social benefits through collaborative processes, are being promoted and applied more and more. The concept and practice of EWN are introduced in this chapter.

Chapter 7, “The Defence of Constantinople,” examines the factors at play in the defense of Constantinople – geography, fortifications, land and naval forces, adequate supply of water and provisions, and, most importantly in the eyes of its inhabitants, the miraculous tutelary powers resident in the God-guarded city.

Chapter 5 discusses actions to alter or remove shore protection structures to help restore landforms and habitats. The case is made for the need for sediment and space to sustain natural features, the need to connect landforms and habitats by sediment transfers, and the need to allow for migration of topographic features offshore, onshore, and alongshore. The importance of coastal erosion in providing sediment and space is highlighted as is the importance of erosional landforms (e.g., bluff faces) as threatened habitat. Managed retreat by removing shore protection structures is evaluated in terms of technical feasibility and stakeholder concerns. Decision support criteria and case studies are provided to assess feasibility of managed retreat. Suggestions are made for altering the dimensions or surface characteristics of protection structures to increase sediment transfers or favor habitat. Burial of hard shore protection structures and other nature-based solutions are evaluated as ways to reestablish some of the natural process-response relationships between waves and currents and faunal interactions and increase the aesthetic and recreational value of the shore.