The A-Kerk (litt. A-Church) is the smaller of two surviving medieval churches in Groningen. It already existed in the 13th century, but it has been heavily damaged and rebuilt several times (war damage in 1594, fire in 1671, collapse of the tower due to bad repair in 1710). The church was extensively restored in 1976-1985, and again (less extensively) in 2006.
The name sounds a bit strange, also to the Dutch. It is named after the Drentsche Aa, a small nearby river. The church is also known as the Der Aa-kerk (of the Aa church), and that became the official name of the church in the 1980s. The original name was Kerk van Onze Lieve Vrouwe ter Aa (Church of Our Lady at the Aa).
The building has not been used as a church for a long time. It is used now as an exhibition and congress centre.
Sources (both sites are available in Dutch only):