The Sea Wall is a dyke that protects much of Guyana's coast from high tide and runs for 280 miles. The so-called "kokers" or sluices are adjusted on a daily basis to allow for controlled water release into the canals. Note the hand crank mechanism and the hanging ballast.
Clearly, the Dutch, who originally settled the area in 1598, eventually known as Stabroek were up to the challenge of fending against the encroaching sea and established the sea wall, canals and kokers (look like guillotines as observed by Guyanese author Melville in Ventriloquist's Tale, p. 36) in 1783. Streets on a grid were laid out at this time. The Dutch continued to rule (with short wartime interruptions by France and Britain) until 1814, when the colony was ceded to the British.
Canals were needed for the sugar cane plantations. Eventually, many of these canals were filled in and now feature promenades lined with shade trees (Royal Poincianas in photo). Cannonball trees, Samaan trees line other promenades. Latin names are Delonix regia, Couroupita guianensis, and Samanea saman.