Camden Lock on the Regent's Canal, next to Camden Market, Camden Town, London, England, United Kingdom, Europe

Aerial of the Canal du Midi near Carcassonne, UNESCO World Heritage Site, Aude, Occitania, France, Europe

Canal du Midi near Carcassonne, UNESCO World Heritage Site, Aude, Occitania, France, Europe

Aerial of the Canal du Midi near Carcassonne, UNESCO World Heritage Site, Aude, Occitania, France, Europe

Detail of the gate of the Kunya Ark, Khiva, Uzbekistan, Central Asia, Asia

Stile and footpath with lock keepers house beyond, on the Worcester and Birmingham canal, Tardebigge, Worcestershire, England, United Kingdom, Europe

A canal going from the sea to the reclaimed polder land which is some 20 feet lower than the sea, north of Amsterdam, Netherlands, Europe

A narrow boat in locks on the Leeds Liverpool canal near Saltaire in Yorkshire, England, United Kingdom, Europe

Europe, Great Britain, England, London, Bobbies at Buckingham Palace

Sluice gate, lock gate Hindenburg, Hannover Anderten, lower saxony, Germany

Lock and houseboats in a canal in Knowle, West Midlands, England, Great Britain, Europe

Locked gate, property owned by a big landowner, Gran Chaco region, Salta province, Argentina, South America

Eider Barrier on the mouth of River Eider near Toenning - largest German coastal protection building, Schleswig-Holstein, Germany

Landeszeughaus armory Herrengasse Graz capital of Styria Austria gate with wrought-iron fittings

Neues Schloss, Ingolstadt, Bavaria, Germany

gate lock

Bear warning sign posted on a closed gate where a trail has been closed, Liard River Hot Springs Provincial Park, British Columbia, Canada