This is one of the most important sites in Cologne ­ and, in fact, the world ­ as it stands in the very heart of the city. The massive church has roots dating back to the eighth century and has been an integral part of the city's history. The massive structure is both beautiful and awe-inspiring. The interior features a range of historic and religious artifacts. For the adventurous, walk to the top of the spire and look over the city. The climb is a definite workout, but the views of Cologne and the Rhine warrant the effort. Truly a must-see for anyone in the city.

Inside what was once a church, this museum features the city's most extensive and breathtaking collection of religious art and ecclesiastical treasures. The church itself, St. Cecilia's, is a graceful example of Romanic architecture, and the pieces inside are primarily from medieval times. Look for tapestries, ivories, old manuscripts, sculpture and much more.

Another of Cologne's beautiful and historic churches. Locals consider this religious site second in importance only to the great Dom. The church's original sections date from the fourth century. The main church building features interesting architectural flourishes. Don't miss the gorgeous stained glass windows that adorn the building's upper sections.

This historic City Center church was built in the 10th century in the highly attractive Romanesque style. The church's west wing features double spires and a gorgeous façade. The style, history and architectural flourishes are all reasons to stop by this site during a walking tour of the city.