The Iglesia de Santiago is one of the clearest traces of Romanesque Sigüenza, tucked into the slope between the cathedral and the castle. Its portal is the main reason to seek it out: simple, rounded, and much older in feeling than the grander buildings around it.
The church has had a hard history, including serious damage in the 20th century, but restoration has made it legible again. It is not a showpiece in the way the cathedral is. It is better than that: a small survival that helps the old town make sense.