As mentioned on the main Group B page, Dortmund would make a good base for this group if you want to stay in one of the host cities. However, accommodation prices in the host cities are sure to be higher than elsewhere, so I've also looked for alternative potential bases for each group that are geographically fairly central and offer good transport links to every venue.

For Group B, I suggest looking at...

Hannover

Hannover is located in north/central Germany, almost due south of Hamburg, west of Berlin, northwest of Leipzig and to the east of the cluster of host cities in the Ruhr District. It is the capital of Lower Saxony, a main intersection of road and rail routes, a major venue for trade fairs and from 1714 to 1837 was closely linked with Britain by royal blood. It was heavily bombed during the war, with about 80% of the central area destroyed. 

Today, its sights include the Royal Gardens of Herrenhausen, the Old Town Hall and the zoo, as detailed on the Tourist Highlights pages of the city's website. You'll also find ideas for things to see and do over at GetYourGuide.

To give you an idea of what it will be like getting around to the Group B venues if you decide to base yourself in Hannover, I've checked out the travel connections and times by train and coach.

By train there are direct connections to every venue (bar Gelsenkirchen), as shown below (all are main station to main station):

Rail connections

All with Deutsche Bahn from Hannover Hauptbahnhof (main station). Click the 'Hannover to...' links for fares.

Hannover to Düsseldorf
Changes: None
Time: 2hrs 37mins

Hannover to Gelsenkirchen
Changes: 1
Time: 2hrs 18mins

Hannover to Hamburg
Changes: None
Time: 1hr 16mins

Hannover to Leipzig
Changes: None
Time: 2hrs 39mins

Hannover to Berlin
Changes: None
Time: 1hr 53mins

Depending on how many train journeys you're going to be making, rather than buying train tickets separately for each one, it may work out cheaper for you to get an Interrail pass, which you could also use for your travel to and from Germany.

As an alternative to Deutsche Bahn trains, also take a look at Flixtrain, whose rail network covers Hannover and links to all Group B venues. Many of their fares are less than €10.

For fans travelling on a very tight budget, I've also looked at coach travel, which can be really cheap. At the time of writing, for instance (October 2023), you can travel all the way from Hannover to Berlin for under €15, Here are the journey times:

Coach connections

Unless stated otherwise, all are by FlixBus coach from Hannover coach station (behind the main railway station). Click the 'Hannover to...' links for fares.

Hannover to Düsseldorf
Changes: None
Time: 2hrs 54mins
Note: By FlixTrain from main station to main station

Hannover to Gelsenkirchen
Changes: None
Time: 3hr 5mins
Note: Goes to the central coach station (in front of the main railway station).

Hannover to Hamburg
Changes: None
Time: 2hrs
Note: Goes to the central coach station (50m from the main railway station)

Hannover to Leipzig
Changes: None
Time: 3hrs 55mins
Note: Goes to the central coach station (next to the main railway station)

Hannover to Berlin
Changes: None
Time: 3hrs 15mins
Note: Goes to the central coach station (10 minutes from the stadium)

Accommodation

Hotels 

Central-Hotel Kaiserhof
Opposite the station. 4-star style. Coffee and cakes to piano music each afternoon. Food available at all times.

Grand Palace Hotel Hannover
4-star hotel 700m from the station. 24-hr reception. Free Wi-Fi.

Concorde Hotel am Leineschloss
10 minutes by foot from the station. Modern rooms decorated in pastel shades. Free Wi-Fi.

For more options, see the Booking.com Hannover page and/or Germany's two biggest hotel booking portals Hotel.de and HRS.de.

Holiday flats

City Appartement 1 Hannover Altstadt
Holiday flat in the old town. <1000m from the station. Sleeps 2. Kitchen. Balcony.

limehouse Hannover Bleichenstrasse
Suites sleeping up to 4. Kitchen units with fridge, hob, coffee machine etc. 1300m from station.

Apartment City Lenausstrasse
Rooms with kitchen units, microwave, fridge and hob. Sleep 2.

Hostels

Center share Rooms
2.5km from the main station. Bunk beds in mixed dorm. Free Wi-Fi. Balcony.

goodHostel Messe
A 5-minute walk, then 20 minutes on the underground to Hannover main station. Twin and triple rooms.

Campsites
As I've said elsewhere, I've not slept on a campsite for many years, so this isn't my area of expertise. What I've done, therefore, is look for sites with good public transport links to Hannover, from where you could take the coach or train to the match venue as shown above. On that basis, here are a couple of suggestions:

Camping Arnumer See
Near to a small lake, where swimming is allowed. 40 minutes by bus and tram to Hannover main station.

Campingplatz Birkensee
Located close to a sandy lakeside beach. Around 45 minutes by bus and rail to Hannover main station, including a fair walk.

For other campsites in the Hannover area, see Eurocampings and Camping Info.

So, that's Hannover - one option as a base for Group B. If you do, however, prefer to base yourself in one of the host cities, then, as mentioned above, for this group the city to look at is probably Dortmund.