Johan Carl Ludvig Engel (German Johann Carl Ludwig Engel, July 3, 1778 Berlin, Kingdom of Prussia – May 14, 1840 Helsinki, Grand Duchy of Finland) was a German architect who worked from 1816 in the Grand Duchy of Finland. His architecture represented the neoclassical empire style. Engel created a monumental center for Helsinki, which was elevated to the capital, and acted as a trendsetter for the entire Finnish architectural art in the first half of the 19th century.

Prussian-born Engel worked in Berlin, Tallinn and St. Petersburg before moving to Finland. First as the architect of the Helsinki Reconstruction Committee and later as the director of the Intendant's Office, he gained wide influence and unique opportunities to realize his architectural visions.

Engel's main work in Helsinki is the empire milieu of Senate Square, which includes the Helsinki Cathedral, the State Council Castle, the main building of the University of Helsinki and the National Library. He also designed a lot of churches and public buildings in different parts of Finland and drew grid layouts of several cities, such as Turku and Porvoo.

Engel's heritage deals with the history of state and municipal buildings and the cultural heritage of public construction. The content of the book is divided into four chapters: Buildings - the image of society, Building skill and art, Time of change and Engel's legacy. As authors, e.g. Henrik Lilius, Matti Klinge, Pentti Routio, Hannu Taanila, Matti J. Kuronen, Kaj Nyman, Helena Sormunen, Ranko Radovic, Reijo Korhonen, Matti Loukola, Henri Broms, Marjatta Salmenkari, Riitta Kuoppamäki, Eero Paloheimo, Christer Wadelius, Kjell Brevik, Jørgen Skov, Seindor Gudmusson, Eea Pekkala-Koskela, Leena Saarisalo and Matti K. Mäkinen. The richly illustrated book presents the history and architectural development curves of our public buildings with both drawings and photographs.