The Firth of Forth is the estuary, or firth, of several Scottish rivers including the River Forth. It meets the North Sea with Fife on the north coast and Lothian on the south.
The Forth bridges looking northeast
From left to right: The Queensferry Crossing, the Forth Road Bridge and the Forth Bridge from the South Queensferry side
The Fife–Edinburgh hovercraft service
The Ro-Pax ferry Blue Star 1 passing under the Forth Bridge in the Firth, en route from Rosyth to Zeebrugge
An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environments and are an example of an ecotone. Estuaries are subject both to marine influences such as tides, waves, and the influx of saline water, and to fluvial influences such as flows of freshwater and sediment. The mixing of seawater and freshwater provides high levels of nutrients both in the water column and in sediment, making estuaries among the most productive natural habitats in the world.
Río de la Plata estuary
New York–New Jersey Harbor Estuary
River Exe estuary
Estuary mouth located in Darwin, Northern Territory, Australia
