What should I have done? (almost hit horse and rider with my car)

It will stay with you and although nothing bad actually happened, the fact the rider was angry and you got a shock will keep that in your head. You will now know that you need that extra bit of care.
I past my driving test in my 30s a few months later I had a near miss on a double mini roundabout where I nearly knocked a lad off his moped. He wasn't aware but I REALLY was and it really frightened me. I got to work and had to sit down, properly shaking, BUT it has made so much more observant in looking out for bikes. This was about 18yrs ago and I still shudder when I think about it!

National speed limit (NSL) absolutely is not the same as '60 mph limit'

NSL means that you have to make the choice yourself as to the maximum speed appropriate to the road. It is very rarely anywhere near 60mph. A single track rural road with sharp bends is NSL but it would never be safe to be doing 60.

NSL is very poorly understood by the majority of drivers unfortunately

Just to add OP, as a horse rider and owner, and car driver...if I was going round a blind bend on my horse I'd make every effort to get out of the bend ASAP for this very reason. Fir me, I'd be aware going into the bend what was behind me, then trot round the bend and along the road.

Yes drivers have a responsibility to drive according to the road, but as a very vulnerable road user, horse riders also have a responsibility to ride defensively on the road.

It always amazes me that the speed limit rises to 60 on country lanes that are frequently bendy. (Not having a dig at you OP, I’m genuinely amazed, as I think that some of the twists and turns are very sharp, some unexpected, so I tend to treat them with caution, and wonder why on earth they set the speed limit at 60 on these roads). If they were straight roads, where visibility is clear, I could understand it. Country lanes, by their nature, will often have horse riders, cyclists and tractors on them, and will not be straight roads, so to me the 60 mile limit is ludicrous.

The speed limit is a limit NOT a target.
you should drive to the conditions rain, darkness, vision. You should not be doing 60 if you can’t see what is in front of you. Sorry but it’s as simple as that.

Blind corner, country road. Always assume there's a tractor, cyclists, horses round the corner. I've seen a horse hit by a car, absolutely horrific.

The horse and rider were lucky you weren't some yob in a BMW. She wasn't happy but how different this could have been. She (and horse) were actually lucky imo.

I am a horse rider and need to to ride a little bit on the road to access the bridleways in nearby woods.
Thankfully you did act quick. I wish there should be more road signs making drivers aware there could be horses on the road so drivers could expect this and drive more cautiously. I wear high viz at all times so we stick out.
Hope you and the rider/horse are not too shaken.
In general I wish drivers would expect the unexpected especially in rural roads

40mph is very fast for a bend. Even 30 is too fast.

Pay more attention to the road conditions (straight, bends, ability to anticipate oncoming traffic) and remember posted speed limits are not targets but maximum allowed in excellent conditions.

Because everyone driving on the roads should have a driving license having passed a driving test to show they understand how to drive around vulnerable road users.

Everyone driving should do so within the terms of their license which includes safety around vulnerable road users.

It can be terrifying at times & most would not choose to do it if there were an alternative, but there often isn't.

Horses aren't allowed on footpaths or pavements & the bridleway network is cut up by roads.

This. You’ve taken the advice well OP but it’s incredibly concerning that it’s never occurred to you before! Horses, pedestrians, queue's of traffic, tractors , an accident- anything could be round a blind bend.

A couple of years ago a DPD courier killed two horses near me driving too fast up a country lane. Two riders were in hospital for weeks with broken bones. If it's something you've never seen before, pray you never do.

Was it a rural road at national speed limit?

If so this doesn't mean that 60mph is acceptable & there is a lot of misunderstanding of what NSL means. It just means you need to drive to the conditions. Doing 40mph around a blind bend on a single track road is too fast. You needed to do an emergency stop so you were going way too fast. If you had been involved in a collision then you would likely have been charged with dangerous driving (or worse had you killed the person leading the horse)

Single track NSL rural roads have the highest risk of death of all roads in the UK (far higher than motorways)

Locally to us a lot of single track NSL rural roads are being changed to 30 or even 20.

As you were shaken by it & have reflected on it & learned from it I think you just need to move on from it. It's the people who think they have the right to drive at speed & everyone else (cyclists, horses etc) need to get off the road that are most dangerous.

I was almost taken out by a car on a blind bend while on a horse. Could hear her gunning down tiny lane, so quickly moved to outside of road, so at least she saw me before it was too late. She did emergency stop, then berated me for not thanking her for stopping! She had a saddle in back of massive Range Rover - so a rider presumably 😳

Always predict danger around a bend just in case! Xxx

Drivers don't need more than a few seconds if they are driving at the correct speed for the road.

Most people riding a horse don't choose to ride on the roads unless absolutely necessary. But often to go somewhere for a proper ride, you need to get from where the horse is kept to somewhere where you can ride. Which sometimes. Not always, but most often. Requires Riding on country roads to get to.

They don't do it for the share fun of it,

The OP may have owned her mistake, but she's accusing other people of driving too fast around the bends. Hypocrisy does need calling out.

Well, some of us don't really have the option if the pavementless, bendy stretch of road is part of our journey, and we can't drive and there is no public transport. But yes, much worse to be a horse and having to do it because a human being decides on your behalf!

This is so true, and while we have the option of walking or not walking on these types of roads, the horses do not.

Yes.

Yes, that’s probably a good idea.

And thanks for posting about this and raising awareness. I have a terrifying time walking on sections of local country roads without pavements, where the drivers assume that the road beyond every single blind corner is clear and available to them to take at speed. I have to cross the road sometimes so that oncoming traffic is behind rather than ahead of me when the bend goes a particular way; safer but still not safe.
Roads are not just for cars and lorries, they are for everyone.

While I would go carefully around the corners on windy country roads, I also think that some vulnerable road users are careless of their own safety and sometimes quite selfish.

SW Highways have a warning advert which basically says that just because you know the roads really well doesn't mean you know what traffic is going to be on it.

Lucky escape, learn from your near miss!

I really think they should put a more sensible limit on place on them. Around here you could encounter horses, escaped sheep and cows, pedestrians with prams or dogs, cyclists. I go slowly around corners and never even approach 60.