The Puerta de la Ciudad (City Gate) is a large castle-like structure built at the northern entrance to the colonial centre in the 1990s — a deliberate evocation of the city's centuries-old tradition of celebrating its civic independence. The structure contains a small museum of local history and offers views from its towers over the city and the surrounding valley.
It is a slightly eccentric piece of civic architecture, but the towers provide a good orientation point when arriving in Loja, and the museum inside gives a reasonable overview of the city's history before you set off to explore the streets below.