Blauwpoortplein Dordrecht Netherlands Panorama by Hendrik-Jan Kornelis

The Blauwpoort was a city gate in the South Holland city of Dordrecht on the present-day Blauwpoortsplein. The gate stood on the Nieuwe Werk, the early 15th-century land reclamation on the Nieuwe Haven, close to the Engelenburg Bridge, connecting the Nieuwe Werk with the Lange Geldersekade and the rest of the area around the Grote Kerk. In 1662, this bridge is called the "brugge byde blauwe poorte".

The first mention of the Blauwpoort dates back to 1555 ("blaeuwe poort"). The name was derived from the natural stone used in its construction. The then probably fairly new gate is depicted on Jacob van Deventer's city maps from the mid-16th century and also on later maps. However, the exact location and orientation of the gate are not entirely clear. Next to the gate - as with the Melkpoortje - was a "blau bolwerck", named after either the Blauwpoort or the natural stone ("blau steen") with which the bulwark was partly constructed. This blue bastion is mentioned in 1577 in the passage: "on d'kaeye buyten de poort [=Blauwpoort] van het nyewe werck naest blau bolwerck binnen dese stede."

Based on copies of old drawings, the gate in the background of The Lyre Man by Dordrecht painter Nicolaes Maes recognises the original, 16th-century Blauwpoort. This was replaced in 1672 by a large gatehouse of red brick in late, austere Dutch-classical style. This second "blaauwpoort" (as it was still called in 1706) was demolished in 1910.