Germany

I'd be happy to help you plan your 7-day trip to Germany. Here's an itinerary that includes Berlin and Munich, while keeping costs as low as possible:

Day 1: Arrival in London

You'll arrive at London Heathrow Airport (LHR) from San Francisco (SFO). You can spend the day exploring London or resting up for your flight to Berlin the next day.

Day 2-4: Berlin

Take a morning flight from London to Berlin. Spend the next three days exploring this vibrant city. Some must-see attractions include the Brandenburg Gate, Checkpoint Charlie, the Berlin Wall, and the Reichstag Building. You can also visit some of Berlin's world-class museums, such as the Pergamon Museum or the Jewish Museum. In the evenings, check out the city's nightlife scene, which is known for its techno clubs and beer gardens.

Day 5-6: Munich

Take a train from Berlin to Munich, which takes about 4 hours. Spend the next two days exploring this beautiful Bavarian city. Visit the Marienplatz, the Hofbräuhaus beer hall, and the Nymphenburg Palace. If you have time, take a day trip to Neuschwanstein Castle, which inspired the design of Disney's Sleeping Beauty Castle.

Day 7: Departure

Fly back to London from Munich and then catch your flight back to San Francisco.

Overall, this itinerary gives you a good taste of both Berlin and Munich, while keeping costs low by taking advantage of budget airlines and trains. Of course, there are many other things to see and do in Germany, so feel free to adjust the itinerary to suit your interests and preferences.