How best to put this (with apologies to Douglas Adams):
Ascot is big, you have no idea how amazingly vastly hugely big Ascot is, you might think it's a long trip around Woodbine's 1.5 mile turf course, but that's peanuts compared to Ascot:
The basic course is a triangle with 2 chutes:

Note that the chute on the right is a "1 mile start" -- for comparison, Churchill Downs main track is a mile in circumference, Belmont park's main track is a mile and a half. Mile and a half (1mi, 4f) races at Ascot start on the left hand leg of the triangle. The triangle part of the track is about 1-3/4 miles. There is also the "old" mile course which starts at the top of the picture and goes around the corner to the finish line.
Here are some shots taken at the track (as a point of information, 3 of the 4 days of Royal Ascot I was in the Royal Enclosure where photography is forbidden. The bulk of the pictures on the Ascot portion of this saga are taken in Members enclosure).

Here's the start of the straight mile:
The starting line isn't where those people are crossing the track, that's just the people entering from one of the parking lots. The start is where the black arrow is.



You probably think I'm standing near the finish line, but I'm not, (I'm about at the quarter pole) here's a shot taken from just about the same spot looking towards the finish line:

again, the finish line is noted by the arrow. The little watch towers are for the race officials.

Like I said, the track is BIG!

Because of its size, the fact that "Swinley Bottom" ( the top of the triangle part of the course) is about 20' lower in altitude than the finish line (yes, that means that the "Old Mile" is an uphill run) and the lack of Jumbotrons (although there are TV's inside the stands) binoculars are a must -- powerful binoculars, my 8x25's which have served me well at many US tracks were barely adequate at Ascot, particularly as the horses rounded Swinley Bottom.

Because the track is big they can have some big races. For races that are run on the straight mile (and shorter races that use the same part of the track), there can be up to 32 starters in a single race. For those of you that find that hard to believe (as I did until I actually saw it), here is a picture of horse #30 heading out to the post:

Nancy and I took to calling these races "cavalry charges", especially the 3/4 mile Juvenile races (Think about trying to handicap 32 2-year olds running straight for 6 furlongs -- we stopped trying after the first few).

Also there are only 6 races each day (this seems standard for England, at other tracks there were 6 or 7 races per day), and the 3rd race each day is the feature race (if the feature race is a 3-year old race there is also a "feature handicap", which is the 4th race).