In Cologne, must do's include everything from the largest cathedral in Germany to a touring the city's many breweries. Here are 5 must see destinations in Cologne that you'll definitely want to add to your itinerary.

Cologne Cathedral

This incredible Gothic church, as it stands now, is a continuing work in progress that began in the year 1248. However, the site on which it stands has been used for church grounds since much earlier. Of particular interest to visitors are the relics of the magi, brought to the cathedral in 1164. You can visit daily from 06:00 to 19:30 from November through April and until 22:00 from May through October. Entrance is free, but is prohibited during mass times. You can also ascend to the bell tower or descend to the treasure chamber. Tickets for the tower are €2,50 for adults and €1 for children. Tickets for the treasure chamber are €4 for adults and €2 for children. Or, you can purchase a combined ticket for €5. Dial +49 (0)221 92 58 47 20 for information.

Botanical Gardens and Zoo

The botanical gardens house over 10,000 species of plant life including flowers, shrubs and trees. There are also several greenhouses on the premises, including a palm tree house. In the center of the gardens you'll find the Haus Flora, complete with restaurant and dancing. The gardens are open from 08:00 to dark, with the houses being open from 10:00 to 16:00 from October through March and from 10:00 to 18:00 from April through September. Admission is free. Just next to the gardens is the Cologne Zoo, housing an impressive amount of wildlife. The zoo is open from 09:00 to 18:00 in the summer, closing an hour earlier in the winter. Tickets are €13 for adults and €6 for children. Dial +49 (0)221 77 85 121 for information.

Roman-German Museum

The Romisch-Germanisches (Roman-German) Museum is located just across the way from the cathedral and is one of the more interesting museums in Cologne. It houses artifacts from the Cologne area dating from Prehistoric times through the Roman and Germanic periods. The museum is open from 10:00 to 17:00 and tickets are €7 for adults and €4 for children. They can be reached at +49 (0)221 22 12 44 38.

Neumarkt Galerie Shopping Center and Street Shops

The Neumarkt Galerie is the premier shopping center in Cologne, but even more fun is the trip from Cologne Cathedral down Hohe Strasse and Schildergasse to reach the Galerie. Hohe Strasse was the first pedestrian shopping street in Germany, and today it and Schildergasse remain filled with stores and boutiques that sell a variety of wares from fashion to household goods, complete with numerous cafes and restaurants. Expect shops to be open from about 10:00 to 20:00. You can reach the Newmarkt Galerie at +49 (0)221 20 59 21 00.

Brewery Tour

Once known for having the most breweries in a German city, Cologne now has but a handful of breweries left. However, the famous brand, Kolsch (meaning "of Cologne") lives on in the many pubs and restaurants. You can still visit a few of the remaining breweries, including Paffgen and Sunner. Paffgen is open Monday to Friday from 07:00 to 15:00 and Saturday from 09:00 to 12:00. It can be reached at +49 (0)221 13 54 61. Sunner is open Monday to Thursday from 07:30 to 16:00 and Friday until 14:00. The phone number is +49 (0)221 98 79 90. Don't forget to pick up a specialty Kolsch glass as a souvenir!