Archidona is a quiet colonial town ten kilometres north of Tena, founded as a Spanish mission in 1560. It is easily reached by bus or taxi and makes for a pleasant half-day excursion. The town's painted church is worth a visit — its interior murals blend Catholic imagery with Amazonian motifs in a way you will not see elsewhere.
The surrounding area has several caves and waterfalls accessible by short hikes, most notably the Cuevas de Jumandy, a network of underground river caves that you can wade through with a guide and a headlamp. The caves are popular with locals on weekends and nearly empty midweek.