Vilbel Castle, Medieval castle in Bad Vilbel, Germany.

Vilbel Castle is a medieval fortress in Bad Vilbel situated along the Nidda River, defined by thick defensive walls and a water-filled moat. The structure displays the typical features of a fortified stronghold with clear defensive elements that highlight its historical role as a protective settlement.

The structure originated in the 12th century but was destroyed in 1399 and subsequently rebuilt on a larger scale. Another major setback came in 1796 when French revolutionary forces under General Kleber damaged the fortress during military campaigns.

Since 1987 the courtyard has hosted the annual Burgfestspiele Bad Vilbel, a summer theatre festival. The name Vilbel first appears in a 774 charter donating the site to Lorsch Abbey. The castle ruin is a Hessian cultural monument, cited as a rare 15th-century example of a Wasserburg in Hesse.

The moat is filled with water, and its seepage has damaged the masonry, so restoration work has been under way; on 10 July 2024 a corner broke out of the wall on the side facing away from the audience. The courtyard hosts the Burgfestspiele each year, and repairs begin after the season ends. Check access to the ruin before planning a visit.

The moat around the ruin was only filled with water after the city acquired the castle; the water later damaged the masonry and forced costly repairs. Researchers now believe the medieval ditch was normally dry and flooded only when danger threatened. On 10 July 2024 a corner broke out of the wall on the side facing away from the audience.