The neoclassical church of Askainen was built by the owner of Louhisaari Manor, Governor-general Herman Claes'son Fleming in 1653 as the chapel church of Louhisaari Manor. It’s one of the rare stone churches in Finland built after the Reformation in the 17th century. The belfry was erected in 1772–1779. There is a funeral chapel of the Mannerheim family in the cemetery.
The Askainen noblemen's church is part of the oldest tourist route in Finland, the Seven Churches Tour, together with Raisio, Masku, Nousiainen, Lemu, Merimasku and Naantali. Finnish National Board of Antiquities has named the church and near Louhisaari manor as National Built Heritage.
The Church of St Eustace was built between 1532-1632. St Eustace"s is considered a masterpiece of late Gothic architecture. The church’s reputation was strong enough of the time for it to be chosen as the location for a young Louis XIV to receive communion. Mozart also chose the sanctuary as the location for his mother’s funeral. Among those baptised here as children were Richelieu, Jeanne-Antoinette Poisson, future Madame de Pompadour and Molière, who was also married here in the 17th century. The last rites for Anne of Austria, Turenne and Mirabeau were pronounced within its walls. Marie de Gournay is buried there.
The origins of Saint Eustache date back to 13th century. The church became a parish church in 1223, thanks to a man named Jean Alais who achieved this by taxing the baskets of fish sold nearby, as granted by King Philip Augustus. To thank such divine generosity, Alais constructed a chapel dedicated to Sainte-Agnès, a Roman martyr.