Flypast fans prepare yourselves - this is the big one.
The 75th anniversary of the Battle of Britain will be marked today (15 September) by the largest flypast of Spitfires since World War II, alongside a service at St Paul's Cathedral.
In total 40 Spitfires, Hurricanes and Blenheims will commemorate the series of skirmishes that took place in the skies thousands of feet above the south coast of England in 1940.
Read more: The Battle of Britain flypast - in pictures
Not only that, but there will be a royal guest of honour taking part.
Prince Harry will join veterans of the battle, flying in a two-seater Spitfire from Goodwood Aerodrome in West Sussex.
The planes will fly across the south of England from 12pm over towns that were bombed by Nazi aircraft and the airfields that played such a key role in the battle.
Here are the routes:
Let's hope the sun comes out in time.