Here I am, just about to turn left to avoid flying over Parliament. Her Majesty's Government doesn't like it and I can't blame them.
This time, I followed the railway line from the southeast to London Victoria, which is just to the north-west of Parliament. Urban griffins like myself have been using the railways to navigate ever since they were first built in the 19th century. We also use rivers, canals, motorways and other landmarks to navigate when we go from city to city.
When dealing with international borders, we have to land, enter the post on foot, present our passports and submit to a search like everyone else (a lot of griffins find good work as couriers, you see... and some are not above smuggling). After we lawfully cross the border, no one really argues if we just take off again.