Reconnect with your spiritual side and meet other worshippers at St. Gallus Church. Sit in quiet reflection outside for a while or ask if you are allowed to join the next service.
You're spoiled for sightseeing choice when staying in Tuttlingen. St. Gallus Church is a great place to kick off here, but there are numerous other fine attractions to check out. Honberg Castle, Swabian Alb Route, and City Garden are close to the house of prayer and will fill in your day nicely.