Lake Sääksi

{{short description|Lake in Uusimaa, Finland}}

{{Infobox body of water

| name = Lake Sääksi

| native_name = {{langx|fi|Sääksjärvi}}

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| image = Sääksjärvi (Nurmijärvi) beach.jpg

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| caption = A sandy beach of Lake Sääksi

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| location = Uusimaa

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| basin_countries = Finland

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| area = {{convert|2.6|km²}}

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| max-depth = {{convert|8.5|m}}

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| cities = Nurmijärvi, Hyvinkää

| pushpin_map = Finland

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| pushpin_map_alt = Location of the former lake in Finland.

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Lake Sääksi ({{langx|fi|Sääksjärvi}}, or just simply Sääksi) is a 260-hectare large lake in Uusimaa, Finland.{{cite web|url=https://www.jarviwiki.fi/wiki/S%C3%A4%C3%A4ksj%C3%A4rvi_(23.097.1.002)|title=Sääksjärvi (23.097.1.002)|website=jarviwiki.fi|access-date=23 July 2023|language=fi}} It is located on the border between the municipalities of Nurmijärvi and Hyvinkää, on the ridge formation called Salpausselkä.{{cite web|url=https://www.visitnurmijarvi.fi/fi-FI/topic/6234798ecccf6550e250535d?mode=listings&count=9|title=Sääksi - Kirkkaasti kauneinta Suomea|publisher=Visit Nurmijärvi|access-date=23 July 2023|language=fi}} The villages of Röykkä and Kiljava is located near Lake Sääksi.

Lake Sääksi is a groundwater lake without a drainage ditch, and its water changes through the soil. The lake is very even in depth and the deepest part of the lake is about eight meters deep. The water in the lake is very clean, and the lake has a good oxygen situation. Alkalinity, which indicates the buffering capacity of lake water, is very low. Lake Sääksi is one of Finland's largest spring-based lakes.{{cite web | url = http://www.ess.fi/?article=325424 | title = Suomen suurin lähde löytyy Lapista | work = Etelä-Suomen Sanomat | access-date=23 July 2023|language=fi}}

The approximately 800-meter-long Sääksi Beach is popular especially among the residents of Nurmijärvi and Hyvinkää, but it also attracts visitors from other parts of Uusimaa.{{cite web|url=https://www.hs.fi/kaupunki/art-2000004575299.html|title=Sääksjärvessä uidaan kirkkaassa lähdevedessä|work=Helsingin Sanomat|url-access=subscription|date=7 June 2008|access-date=23 July 2023|language=fi}}{{cite web|url=https://www.nurmijarvenuutiset.fi/paikalliset/4205953|title="Lähiseudun paras uimaranta" – Sääksjärven uimaranta kerää helteistä nauttijoita kauempaakin|work=Nurmijärven Uutiset|date=30 June 2021|access-date=23 July 2023|language=fi}}

The lake has been said to have served as a model for fictional Lake Ilvesjärvi in the 1870 novel The Seven Brothers by Aleksis Kivi.{{cite web|url=https://www.hs.fi/hyvinvointi/art-2000008881816.html|title=Kirkkaana kiiltävät vedet|work=Helsingin Sanomat|url-access=subscription|date=16 July 2022|access-date=23 July 2023|language=fi}}