The architectural plans for the monastery of Reichenau date to sometime between 819 and 826. Some 1,200 years later, the public can now see the pioneering construction sketches for the first time.

The UNESCO World Heritage site library that hosts the so-called 'Plan of St Gall has now put the seminal planning sketches on display as part of a permanent exhibition. 

The 112 metre x 77.5 metre parchment is part of an exhibition at The Abbey of St Gall, which was opened on Friday April 12th in the presence of Switzerland's Federal Councillor Alain Berset. 

“Here it becomes clear: History not only reveals past events, but also reminds us that this was once a future,” tweeted Berset after the exhibition's opening. 

An open day for the public with additional talks and art and music events will be held on Saturday April 13th starting at 10am. 

“The Convent of St Gall, a perfect example of a great Carolingian monastery, was, from the 8th century to its secularization in 1805, one of the most important in Europe. Its library is one of the richest and oldest in the world and contains precious manuscripts such as the earliest-known architectural plan drawn on parchment,” states UNESCO's website. 

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The library contains 170,000 books as well as 2,000 original manuscripts from the Middle Ages, according to a report by Swiss daily 20 Minutes. 

The Plan of St Gall does not reflect the current form of the abbey, although it is revered as a pioneer of modern architectural drawing. 

“The Plan of St. Gall is the earliest preserved and most extraordinary visualization of a building complex produced in the Middle Ages,” according to the dedicated website of the library that hosts it. 

The medieval abbey was rebuilt between 1755 and 1768 in the Baroque style.

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