The Burcht van Leiden is an old shell keep in Leiden constructed in the 11th century. It is located at the spot where two tributaries of the Rhine come together, the Leidse Rijn, and another river, now a canal. The structure is on top of a motte, and is today a public park.
From humble beginnings, the hill was raised during various periods of history up to 9 meters above the surrounding landscape in the 11th century. Ada van Holland used the keep as a residence until her father died in 1203 and she was captured by her uncle. In the same year the previous stone building was rebuilt after an attack on the castle, with tuff stone, and after Ada's removal, in 1204 it was attacked again and rebuilt with brick.
Later in the 13th century the building was considered antiquated, since more and more townspeople and houses were built around the base of the hill, making defenses impossible without destroying most of the city. The old 'interior keep' that had been built against the interior walls (a similar ronded keep construction can still be seen in Teylingen) was slowly dismantled and reused for city construction.
As the city of Leiden grew around it in the 13th and 14th centuries, the ruined castle lost its military function. The location became a romantic patriotic symbol after the Siege of Leiden in 1574. In 1651 the city bought the premises to make it into a water tower for public use. A system of waterpipes leading to squares in the city is still intact. In this period a new portal on the keep wall was designed in 1662 with heraldric symbols by Rombout Verhulst, denoting the leading families of the city. There are two other gates to the Burcht, one at the base of the hill with wrought iron heraldric weapons, built in 1653, and one on the south side of the complex, which itself forms a gateway to the park.References:
Monte d"Accoddi is a Neolithic archaeological site in northern Sardinia, located in the territory of Sassari. The site consists of a massive raised stone platform thought to have been an altar. It was constructed by the Ozieri culture or earlier, with the oldest parts dated to around 4,000–3,650 BC.
The site was discovered in 1954 in a field owned by the Segni family. No chambers or entrances to the mound have been found, leading to the presumption it was an altar, a temple or a step pyramid. It may have also served an observational function, as its square plan is coordinated with the cardinal points of the compass.
The initial Ozieri structure was abandoned or destroyed around 3000 BC, with traces of fire found in the archeological evidence. Around 2800 BC the remains of the original structure were completely covered with a layered mixture of earth and stone, and large blocks of limestone were then applied to establish a second platform, truncated by a step pyramid (36 m × 29 m, about 10 m in height), accessible by means of a second ramp, 42 m long, built over the older one. This second temple resembles contemporary Mesopotamian ziggurats, and is attributed to the Abealzu-Filigosa culture.
Archeological excavations from the chalcolithic Abealzu-Filigosa layers indicate the Monte d"Accoddi was used for animal sacrifice, with the remains of sheep, cattle, and swine recovered in near equal proportions. It is among the earliest known sacrificial sites in Western Europe.
The site appears to have been abandoned again around 1800 BC, at the onset of the Nuragic age.
The monument was partially reconstructed during the 1980s. It is open to the public and accessible by the old route of SS131 highway, near the hamlet of Ottava. It is 14,9 km from Sassari and 45 km from Alghero. There is no public transportation to the site. The opening times vary throughout the year.