Before the arrival of the Teutonic Knights, Koknese was the site of a wooden hill fort inhabited by the Balts. In 1209 Bishop Albert of Riga ordered the construction of a stone castle at the site, naming it Kokenhusen. For the first 50 years of its existence, Koknese was solely used as a defensive fort, but by 1277, Koknese had enough population to receive city rights. Koknese also became a member of the Hanseatic League thanks to its strategic location on the Daugava trade route.
The castle was heavily contested between Polish, Swedish and Russian forces in the 16th and 17th centuries. It changed hands many times, while the native inhabitants endured periodic slaughter, capture, and famine. In 1701, during the Great Northern War, Koknese was finally blown up by retreating forces to avoid the strategic castle falling into advancing Russian hands. The castle was never rebuilt and fell to ruin.
In 1900, a park was established around the castle ruins, and Koknese became a popular summer resort. The area was known for its scenic waterfalls, cliffs, and look-outs. In 1965, the Soviet government built Pļaviņas Hydro Power Plant in the town of Aizkraukle. The reservoir flooded the entire length of the Daugava to Pļaviņas. Koknese Castle, once sitting atop a high bluff, was placed at the river's edge, while the scenic Daugava valley was submerged.References:
German crusaders known as the Livonian Brothers of the Sword began construction of the Cēsis castle (Wenden) near the hill fort in 1209. When the castle was enlarged and fortified, it served as the residence for the Order's Master from 1237 till 1561, with periodic interruptions. Its ruins are some of the most majestic castle ruins in the Baltic states. Once the most important castle of the Livonian Order, it was the official residence for the masters of the order.
In 1577, during the Livonian War, the garrison destroyed the castle to prevent it from falling into the control of Ivan the Terrible, who was decisively defeated in the Battle of Wenden (1578).
In 1598 it was incorporated into the Polish-Lithuanian Commonwealth and Wenden Voivodship was created here. In 1620 Wenden was conquered by Sweden. It was rebuilt afterwards, but was destroyed again in 1703 during the Great Northern War by the Russian army and left in a ruined state. Already from the end of the 16th century, the premises of the Order's castle were adjusted to the requirements of the Cēsis Castle estate. When in 1777 the Cēsis Castle estate was obtained by Count Carl Sievers, he had his new residence house built on the site of the eastern block of the castle, joining its end wall with the fortification tower.
Since 1949, the Cēsis History Museum has been located in this New Castle of the Cēsis Castle estate. The front yard of the New Castle is enclosed by a granary and a stable-coach house, which now houses the Exhibition Hall of the Museum. Beside the granary there is the oldest brewery in Latvia, Cēsu alus darītava, which was built in 1878 during the later Count Sievers' time, but its origins date back to the period of the Livonian Order. Further on, the Cēsis Castle park is situated, which was laid out in 1812. The park has the romantic characteristic of that time, with its winding footpaths, exotic plants, and the waters of the pond reflecting the castle's ruins. Nowadays also one of the towers is open for tourists.