All Saints' Abbey (Kloster Allerheiligen) was a Premonstratensian monastery founded around 1192 when a wooden chapel was built, which was gradually extended to be a monastery. In 1196 the foundation charter was issued by Duchess Uta of Schauenburg. In 1200 Philip of Swabia recognised the foundation, and in 1204 Pope Innocent III confirmed it. The first abbot was Gerung.
In 1248 canons from All Saints were sent to Lorsch Abbey to turn it into a Premonstratensian monastery, since when Lorsch was counted as a daughter house of All Saints. Another daughter house was set up at Haguenau. Through various gifts and livings, inter alia at Oberkirch and Oppenau, the monastery grew rapidly and became one of the major religious, cultural and political centres of the region.
In 1657 it was raised to the status of 'abbey' by the general chapter of the Premonstratensian Order. In the 18th century it was at the high point of its power. In November 1802 however Margrave Karl Friedrich of Baden dissolved the abbey in the course of secularisation, and took all its possessions.
Large fires, in 1470 and 1555, had already destroyed parts of the premises. In 1804, a last fire, started when a bolt of lightning struck the church tower, finished the job. In 1816 the ruins were sold for demolition and used as a quarry for stone and scrap for churches in the valleys of the Rench and the Acher. The altars and saints' figures are to be found in numerous local churches, for example in Bad Peterstal, Oppenau, Ottenhöfen and Achern. Three statues from All Saints' Abbey are above the gateway of the prince's chapel at Lichtenthal Abbey, representing Saint Helena, Uta of Schauenburg and Gerung.
Not until the end of the 19th century, when tourism finally reached the Lierbach valley and its waterfalls, were any steps taken to secure what was left of the ruins, which were then put into the condition they are in today.
On a rise above the ruins of the monastery complex is a war memorial for the fallen and deceased members of the Black Forest Society (Schwarzwaldverein), raised in 1925 by C.M. Meckel und A. Rickert.
In 1947 the Charitable Union of Mainz acquired the area round about the monastery ruins and built a convalescent home for children there. Since 1978 this has been used as a country holiday centre for schools. In 1960 the Bishop of Mainz built a chapel here that, like the abbey church, is dedicated to the honour of God and All Saints.
Also now on the site are a cafe and a small museum. Below the ruins are the All Saints' Waterfalls ('Allerheiligen-Wasserfälle').
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.