Tunja's founding square, laid out in 1539 and the hub of city life ever since. The cathedral, the Gobernación de Boyacá (the colonial-era government building), the Casa del Fundador, and several other historic buildings all face onto it. The square itself is pleasant but not remarkable — it's the surrounding architecture that rewards attention. On weekends, locals fill the benches and the streets around it come alive with street food.
Start here and radiate out from it; most of the historic centre is within easy walking distance.