Reconnect with your spiritual side and meet other worshippers at Church of the Holiest Saviour. Sit in quiet reflection outside for a while or ask if you're allowed to join the next service.
This Centrum house of prayer is an interesting spot to begin your day of sightseeing. There's lots to explore in the vicinity, including Old Town Square, Royal Castle, and Lazienki Park. Take your time at Church of the Holiest Saviour before hitting up these other fine sights.