Igreja Velha, Unfinished colonial church in São Mateus, Brazil

Igreja Velha is an unfinished stone church in downtown São Mateus with high walls and an exposed arch marking where the main altar was intended. The ruins stand fenced at Anchieta Square along Anchieta Avenue in the city center.

The Jesuits planned Igreja Velha in the early 19th century as the largest church in São Mateus, funded by the municipality. On 6 August 1853, the town council halted work: completing this church would cost over 40 contos de réis and some 50 years, while the smaller church at São Mateus Plaza needed only 8 contos de réis. The shell was left unfinished.

The building materials reveal the city's maritime roots, as stones from ship ballasts and lime from local shell mounds were used in construction. These materials speak to how the region's resources once shaped what people built.

The site is fenced for protection, so it is best viewed from outside. It sits in a central location and is easy to reach on foot.

The mortar binding the stones was made from whale oil and lime, a distinctive building method of colonial Brazil. This unusual mixture helped the structure resist the moisture of the coastal climate.