--- title: Precision Sundial in Grein url: "https://www.donauregion.at/en/oesterreich-poi/detail/430039793/praezisions-sonnenuhr.html" description: "New highlight: an extraordinary precision sundial developed by entrepreneur Michael Fröschl in collaboration with astronomer and sundial maker Werner Riegler." date: 2015-07-24 modified: 2026-03-05 --- # Precision Sundial in Grein Precision Sundial in Grein ============================ Grein, Oberösterreich, Österreich ![](https://assets.tourdata.at/260x195/466964/120C9D28437F8F935E6ECF9DE46ADBAD4A3C63594D2A25BFA966920ADF4776DE/praezisions-sonnenuhr.jpg) AI generated Open copyright © Michael Fröschl, Michael Fröschl Close copyright [ ![Two men are standing in front of the ring-shaped precision sundial, with Grein on the Danube in the background.](https://assets.tourdata.at/x550/466964/120C9D28437F8F935E6ECF9DE46ADBAD4A3C63594D2A25BFA966920ADF4776DE/praezisions-sonnenuhr.jpg "© Michael Fröschl, Michael Fröschl") ](https://assets.tourdata.at/1920x/466964/120C9D28437F8F935E6ECF9DE46ADBAD4A3C63594D2A25BFA966920ADF4776DE/praezisions-sonnenuhr.jpg) Ufer 4360 Grein [ open in Google Maps ](https://www.google.com/maps/search/?api=1&query=Ufer%2C%204360%20Grein "Link will open in a new window") [ Open in Apple Maps ](https://maps.apple.com/place?address=Ufer%2C%204360%20Grein "Link will open in a new window") ![](https://static.ecmaps.de/staticmap.jpg?experience=webarchitektur-meta&lat=48.221313133098633&lon=14.853816032409666&width=991&height=450&project=ttg-osm-summer-original&zoom=2000&server=meta.tourdata.at) New highlight: an extraordinary precision sundial developed by entrepreneur Michael Fröschl in collaboration with astronomer and sundial maker Werner Riegler. What makes this sundial special is the analemma—a curved line that automatically accounts for the seasonal variations in solar time. This allows users to read not only the time but also the date. The production required particularly precise components. The 4.17-meter-wide stainless steel ring had to be manufactured with an accuracy of about one millimeter and then precisely aligned. After assembly, the sundial was extensively tested and calibrated. Initially, the time could be read with an accuracy of about **ten seconds**, and at the opening, it was even accurate to five seconds. As a result, the sundial is considered exceptionally precise. The sundial is now open to the public at the Römerrastplatz in Greiner Hafen and, thanks to its location along the Danube Cycle Path, has become a new top attraction for visitors. [ Contact ](#ttgCollapseKontakt) ---------------------------------- **Precision Sundial in Grein** Ufer 4360 Grein Phone +43 7268 7055Show no. E-Mail [tourismus@grein.at](#mailto) --- **We speak the following languages** German [ Opening hours ](#ttgCollapseOeffnungszeiten) ------------------------------------------------ - always open (24/7) - open to the public [ Arrival ](#ttgCollapseAnreise) ---------------------------------- [ Suitability ](#ttgCollapseEignung) -------------------------------------- - Suitable for groups - Suitable for schools - Suitable for kids (all ages) - Suitable for pushchairs - Suitable for teenagers - Suitable for seniors - Suitable for single travelers - Suitable for families - Suitable for friends - Suitable for couples - Suitable for children **Season**- Spring - Summer - Autumn - Winter [ Accessibility ](#ttgCollapseBarrierefreiheit) ------------------------------------------------- Please get in touch for more information. powered by [TOURDATA](https://www.tourdata.at "New window") [Suggest a change](#mailto) [ ![TOURDATA Logo](https://www.donauregion.at/fileadmin/templates/global/images/Logo-Tourdata.png "TOURDATA Logo") ](https://www.tourdata.at "New window")