Prague Meridian

Time has always been important to the residents of Prague and they even have their own “Old Czech Time”. But long before pocket watches became fashionable people knew what time it was or at least they knew when it was noon. The Prague Meridian is an invisible line but it’s also marked in one special place. The text in the picture is in Czech and Latin but it translates as “the meridian according to which Prague time was controlled in the past”.

A Brief History of Time

Back in 1410 the Astronomical Clock provided the first public method of telling time but it was prone to failure and indeed spent much of it’s life not working.

In 1650 the Catholics in the city decided to erect something called the Marian Column on the Old Town Square. In 1652 following the consecration of the Marian Column, the authorities added a line of stones marking the Prague Meridian and adjoining the column at 14 degrees, 25 minutes, 17 seconds, east. Quite simply if the sun was shining, then when the shadow of the Marian Column was centred on the Prague Meridian it was noon.

A century later and the Klementinum Observatory Tower was built and another century after that (1852) the Klementinum took over the noon time calculation (it was a little less than 0.005 degrees or 1.6 seconds different from Marian Column time but few noticed). This time noon was announced by a bell and somebody waving a flag from the top of the Observatory.

It 1891 a cannon was placed along the Prague Meridian but on the other side of the river in Letna Park. This cannon would be fired when they saw the flag being waved on the Klementinum Observatory Tower. The cannon sounded until 1922.

World War One Changes

In 1914 a place called Kramar’s Villa was constructed at the site of the noon-day cannon on the Prague Meridian and since then it has been the official residence of the Czech Premier (not the President).

In 1918 the Marian Column was torn down so it removed that method of telling the time but fortunately the Astronomical Clock was now quite accurate and people were already carrying watches. For years, you could only tell where the column used to be by a stone marker.

The New Meridian Plate

Prague Meridian marker plate in both czech and latin lined up on the old marian column marker — The Prague Meridian lined up on the old stone marker for the Marian Column

In 1990 during resurfacing work on the Old Town Square it was decided both to mark the original location of the Marian Column, change the line of cobbles to a granite/brass strip and add a Latin/Czech ground plate (pictured at the top). This is what you see today.

The New Marian Column

Prague Meridian with shadow of the marian column almost lined up — The Prague Meridian and the New Marian Column (just before 12pm)

Actually what you see today is the new Prague Meridian connected back to the new Marian Column which was reconstructed in 2020 so allowing for daylight saving (and about 15 minutes of error) you can see the shadow of the column fall on the Prague Meridian just like in 1652.