A tombolo is a sandy or shingle isthmus. A tombolo, from the Italian tombolo, meaning 'pillow' or 'cushion', and sometimes translated incorrectly as ayre, is a deposition landform by which an island becomes attached to the mainland by a narrow piece of land such as a spit or bar. Once attached, the island is then known as a tied island.
Tombolo near Karystos, Euboea, Greece
The tombolo connecting St Ninian's Isle with the Shetland Mainland
Monte Argentario, Tuscany, Italy
Chesil Beach, seen from the Isle of Portland looking towards mainland Dorset
A spit or sandspit is a deposition bar or beach landform off coasts or lake shores. It develops in places where re-entrance occurs, such as at a cove's headlands, by the process of longshore drift by longshore currents. The drift occurs due to waves meeting the beach at an oblique angle, moving sediment down the beach in a zigzag pattern. This is complemented by longshore currents, which further transport sediment through the water alongside the beach. These currents are caused by the same waves that cause the drift.
Curonian Spit, divided between Russia and Lithuania
Dungeness Spit in the Strait of Juan de Fuca, on the U.S. Pacific coast.
Farewell Spit, on New Zealand's South Island