Pompous yet majestic, the Italian Renaissance–style former royal court church Berliner Dom (berlinerdom.de; adult/concession €10/7.50) does triple duty as house of worship, museum and concert hall. Inside it's gilt to the hilt and outfitted with a lavish marble-and-onyx altar, a 7269-pipe Sauer organ and elaborate royal sarcophagi. Climb up the 267 steps to the gallery for glorious city views.
Skip the cathedral museum unless you’re interested in the building’s construction. The sanctuary has great acoustics and is often used for classical concerts, sometimes played on the famous organ. The fee-based audioguide is worth getting for interesting nuggets of historical and architectural information.
Despite its historic swagger, the cathedral was only consecrated in 1905, after Kaiser Wilhelm II decided that the previous version lacked sufficient grandeur. So out with the old, and in with what is still Germany’s largest Protestant church.