Alphen aan den Rijn stands on the Oude Rijn, the branch of the Rhine that formed the northern frontier of the Roman Empire. The fort of Albaniana lay under the present town centre, one of the chain of forts along the Lower Germanic Limes that was inscribed on the UNESCO World Heritage List in 2021. The modern town was formed in 1918 by merging the villages of Alphen, Aarlanderveen and Oudshoorn and has grown into a commuter town of more than 100,000 people; little medieval fabric survives above ground.
What draws medieval and fantasy visitors is Archeon, the museum park opened in 1994 on the south-eastern edge of town. It reconstructs three periods with full-size buildings based on excavations: prehistoric farms, a Roman quarter with a bathhouse, temple and inn, and a medieval quarter of around 1350 whose Franciscan friary, with cloister, kitchen, refectory and dormitory, copies an excavated original from Dordrecht. Costumed staff work the crafts through the season, the 3rd-century Villa of Rijswijk houses the Archeologiehuis Zuid-Holland, and the Roman ships found at nearby Zwammerdam, moved to Archeon in 2017, are being restored on site.
The park is about a 20-minute walk or a short bus ride from Alphen station, which has direct trains from Leiden and Utrecht. Archeon closes for the winter and reopens for the Midwinter Fair, when its Roman inn, bathhouse and medieval cloister become concert venues and the streets fill with market stalls and fires.