It was going there regularly as part of a USG program and actually had a team of American expats living and working there. I had to get them out in 2011 and 2016 during the Arab spring revolutions. In 2017 I had two get kidnapped on a dirt road on their way home from work in the farm country. They both managed to escape by making a run for it when their capturers were not attentive. Some great times there. I haven't been back since 2018 so I may be a little dated. Based on my trips there I offer the following:

1) Don't be stupid and take chances.
2) First thing to do when you get there is go to a pharmacy and get some Antinal. It is a local anti diarrheal and the best stuff for the local strains. The US OTC stuff is useless. Sort of a Seal Team vs Mall Cops mismatch. If you don't need it that's great. But it is good insurance to have if you get in trouble.
3) Learn how to use a bidet and embrace it! Also bring some Prep H wipes. Chances are your asshole will thank me.
4) My motto there is if ain't cooked, don't eat it. No salads no fruits. Bring some protein/breakfast bars. If you get a touch of King Tut's revenge, go into fasting mode. Eat very little and eat the bars you brought. We used to do a roll call in the morning to assure everyone was FWC. FWC for the uninitiated, is Farting With Confidence. Hopefully you stay on FWC status for your trip.
5) OK now that's out of the way, stuff to see/do. A lot depends on your preferences. I'm not a museum guy, I tend to find them boring. OTOH I find the pyramids fascinating and could sit there and marvel at them for hours. Others see them as a big pile of rocks and what's the big deal. So it's what I find interesting that I'll mention.
6) Giza and the light show at night on the Sphinx worked for me. Depending on where you are staying in Cairo, it can be only 15-20 mins away. Also there are pyramids all over the country. Some off the beaten track are cool. Now as mentioned, a personal tour guide is really a great way to see the city. Your hotel will set you up but you'll pay 3-4x the going rate. If interested, I can reach out to some US embassy/US expats I'm still in touch with and get recommendations.
7) Look into Coptic Cairo where Moses was placed in the Nile and see if that interests. There's a synagogue, Mosque and church there. I'm not religious But I found that very interesting.
8) Look into the Hanging Church to see if that interests you.
9) Look in the City of the Dead to see if that interests you.
10) The Khan el-Khalili (or just say the con) is the old market. I enjoy it. Go at night. You must haggle for everything. Never pay first price. It can be exhausting but I had fun with it at first. After a while the haggling just bored me. US cash rules. Vanilla beans and saffron can be good deals. Just know what you are buying and work them.
11) US women seem to like Egyptian cartouches. I know a guy in the Khan if interested. You need to give them a couple of days to make them and they will bring them you your hotel. Again I'll pass along to info if interested.
12) Nothing to offer on Red Sea diving but I understand it's outstanding. 2-3 of the best places in the world to dive. Watch out for the Russians.
13) The most terrified I've ever been in my life is during a cab ride in Cairo. Seen all types of things there. Just don't encourage your driver to rush.
14)Enjoy and don't be stupid. Don't take chances. Don't dress like an American tourist. Be aware of your surroundings.

First and mostly - "La, shukran" (No, thank you), rinse and repeat. Lots of people will try to hand you things and help you get from Point A to wherever. I had some rudimentary Arabic when I went, which went a long way, but that is the most important thing.

I was backpacking at the time, so I don't have much advice on nice stuff. Echo the others on Cairo - craziness, Pyramids, Egypt Museum, the main sites are definitely worth doing. I got lost trying to find the khan al-khalili one day and just wandered around, which was interesting but not necessarily recommended. I actually found the subway to be pretty nice getting a couple places.

Didn't boat trip down the Nile, but Luxor and Valley of the Kings were lifetime highlights. The temples and tombs in and around Luxor are beautifully preserved and made me feel like a fleeting blip in human history more than anything else I've done. It was also the hottest I've ever been, at over 120F in August.

As to Red Sea diving, I understand the towns have changed quite a bit, but 15 years ago, Hurghada was a dump full of rude Russian tourists, Sharm looked like a normal resort town but I just passed through it, and Dahab felt like a paradise after the heat and bustle of Cairo, Luxor and Hurghada. I stayed in a backpacker camp/hostel in Dahab, and found one of the better dive shops I have ever worked with in the town. I understand the hotel/resort options have really built up there, which was already in progress when I visited. I extended my stay there from 5 days to two weeks and got an advanced dive certification, but would have to dig out my logs to remember what all I did (other than the big ticket items like Blue Hole and the Bells). I also did a sunrise bus tour to Mt. Sinai and St. Catherine monastery while I was there.

Happy to weigh in on particular questions if you have them, though with dive stuff especially, 15 years is a lot of time. And overnight buses around the country are probably not how I would travel anymore, but I have thoughts on those as well.

to the proper tourist sites but also had stops at the "Perfume Museum" and "Flying Carpet Museum" which were glorified gift shops selling their obligatory specialities. Make sure to avoid those.

In Cairo the drivers use their horns instead of turn signals and don't really care if anyone else hears or sees them. I found it amusing but some of the more cautious members were slightly distressed. Don't be alarmed if you see various large animal (larger than deer) carcasses not far off the road either.

The passageway going into the pyramid is slightly claustrophobia inducing at at the very end there is nothing but a large chamber, anything of interest was stolen many years ago. Only go inside if you really just want to say that you were there.

I've traveled to more than 60 countries and all kinds of luxury and economy hotels and the only place that I came back from with an acquired parasitic infection was from eating 1 piece of fruit from the gift basket in the high-end Egyptian hotel. Just sayin'.

The Nile boat tour will include a guide at planned stops most likely. You won’t have freedom of choice but that’s fine.

Get a guide with a driver for Cairo. Shouldn’t cost more than $100-150 for that per day.

Get to Saqqara pyramid not just the Giza big three. It’s less crowded and you feel the desert a bit more.

Tourist: Yes I quite agree I mean what's the point of being treated like sheep. What's the point of going abroad if you're just another tourist carted around in buses surrounded by sweaty mindless oafs from Kettering and Coventry in their cloth caps and their cardigans and their transistor radios and their Sunday Mirrors, complaining about the tea - "Oh they don't make it properly here, do they, not like at home" - and stopping at Majorcan bodegas selling fish and chips and Watney's Red Barrel and calamari's and two veg and sitting in their cotton frocks squirting Timothy White's sun cream all over their puffy raw swollen purulent flesh 'cos they "overdid it on the first day."

Bounder: (agreeing patiently) Yes absolutely, yes I quite agree...

Tourist: And being herded into endless Hotel Miramars and Bellvueses and Continentales with their modern international luxury roomettes and draught Red Barrel and swimming pools full of fat German businessmen pretending they're acrobats forming pyramids and frightening the children and barging into queues and if you're not at your table spot on seven you miss the bowl of Campbell's Cream of Mushroom soup, the first item on the menu of International Cuisine, and every Thursday night the hotel has a bloody cabaret in the bar, featuring a tiny emaciated dago with nine-inch hips and some bloated fat tart with her hair brylcreemed down and a big arse presenting Flamenco for Foreigners.

Bounder: (beginning to get fed up) Yes, yes now......

Tourist: And then some adenoidal typists from Birmingham with flabby white legs and diarrhea trying to pick up hairy bandy-legged wop waiters called Manuel and once a week there's an excursion to the local Roman Remains to buy cherryade and melted ice cream and bleeding Watney's Red Barrel and one evening you visit the so called typical restaurant with local color and atmosphere and you sit next to a party from Rhyl who keep singing "Torremolinos, torremolinos" and complaining about the food - "It's so greasy isn't it?" - and you get cornered by some drunken greengrocer from Luton with an Instamatic camera and Dr. Scholl sandals and last Tuesday's Daily Express and he drones on and on about how Mr. Smith should be running this country and how many languages Enoch Powell can speak and then he throws up over the Cuba Libres.

Bounder: Will you be quiet please

Tourist: And sending tinted postcards of places they don't realize they haven't even visited to "All at number 22, weather wonderful, our room is marked with an 'X'.

Bounder: Shut up

Tourist: Food very greasy but we've found a charming little local place hidden away in the back streets

Bounder: Shut up!

Tourist: where they serve Watney's Red Barrel and cheese and onion.......

Bounder: Shut up your bloody gob....

Tourist: crisps and the accordionist plays 'Maybe it's because I'm a Londoner'." And spending four days on the tarmac at Luton airport on a five-day package tour with nothing to eat but dried BEA-type sandwiches and you can't even get a drink of Watney's Red Barrel because you're still in England and the bloody bar closes every time you're thirsty and there's nowhere to sleep and the kids are crying and vomiting and breaking the plastic ash-trays and they keep telling you it'll only be another hour although your plane is still in Iceland and has to take some Swedes to Yugoslavia before it can load you up at 3 a.m. in the bloody morning and you sit on the tarmac till six because of "unforeseen difficulties", i.e. the permanent strike of Air Traffic Control in Paris - and nobody can go to the lavatory until you take off at 8, and when you get to Malaga airport everybody's swallowing "enterovioform" and queuing for the toilets and queuing for the armed customs officers, and queuing for the bloody bus that isn't there to take you to the hotel that hasn't yet been finished. And when you finally get to the half-built Algerian ruin called the Hotel del Sol by paying half your holiday money to a licensed bandit in a taxi you find there's no water in the pool, there's no water in the taps, there's no water in the bog and there's only a bleeding lizard in the bidet. And half the rooms are double booked and you can't sleep anyway because of the permanent twenty-four-hour drilling of the foundations of the hotel next door - and you're plagued by appalling apprentice chemists from Ealing pretending to be hippies, and middle-class stockbrokers' wives busily buying identical holiday villas in suburban development plots just like Esher, in case the Labour government gets in again, and fat American matrons with sloppy-buttocks and Hawaiian-patterned ski pants looking for any mulatto male who can keep it up long enough when they finally let it all flop out. And the Spanish Tourist Board promises you that the raging cholera epidemic is merely a case of mild Spanish tummy, like the previous outbreak of Spanish tummy in 1660 which killed half London and decimated Europe - and meanwhile the bloody Guardia are busy arresting sixteen-year-olds for kissing in the streets and shooting anyone under nineteen who doesn't like Franco. And then on the last day in the airport lounge everyone's comparing sunburns, drinking Nasty Spumante, buying cartons of duty free "cigarillos" and using up their last pesetas on horrid dolls in Spanish National costume and awful straw donkeys and bullfight posters with your name on "Ordoney, El Cordobes and Brian Pules of Norwich" and 3-D pictures of the Pope and Kennedy and Franco, and everybody's talking about coming again next year and you swear you never will although there you are tumbling bleary-eyed out of a tourist-tight antique Iberian airplane...

Cairo is just crazy. Chaos everywhere. No traffic lights and crossing the street is like the wildebeest crossing the rivers during the Great migration. Just follow the crowd.

Definitely visit the Egyptian Museum in Cairo. Just amazing. Tahrir square is worth the visit, especially if you are a fan of modern history. Get pizza hut there (they love their pizza hut in Egypt). We ate at a great restaurants on an island of the Nile in the city. I dont remember the name, but it was right on the south edge of the island at a Sofitel restaurant. It had a great nightlife scene and views of the city around the island.

Obviously you want to visit the pyramids and sphinx. Get ready to be hit by alot of people selling shit. We did a camel ride around the pyramids which was nice. We also paid a little extra to go inside the Great Pyramid of Giza. I wouldn't say its this amazing walk and its a game changer, but its not that much money to do it and I guess its something to say that you did. But, if you are pressed for time, you can skip it.

I was there for a wedding, so alot of us went on a cruise of the Nile, down to Luxor with Abercrombie and Kent. I think it was 5 days. It was fantastic. If you are deciding what type of cruise to go on. It was not a big ship, probably held like 30/40 passengers. Luxor is well worth the visit. Luxor Temple, Valley of the Kings, Temple of Hatshepsut , and Karnak are all must visits.

If you can check out Abu Simbel, thats one place I wasnt able to visit, but its supposed to be great.

Its a wonderful trip, enjoy

Getting around Cairo is an adventure in and of itself. Taxis can be downright terrifying - fast speeds, no seatbelts. Oh, and good luck if you don't speak Arabic. Needed someone's help giving the taxi driver instructions every single time. And the trick about grabbing a card with your hotel's address on it? Doesn't work because most of the cabbies are illiterate.

But the stuff you'll see in Egypt are second to none. Absolutely exhausting trip, but still one of my all time favorites. Egyptian Museum is amazing and not to be missed. Giza is amazing, especially with the juxtaposition of the pyramids with the modern city right up against it. If you can, the trip inside one of the pyramids was really fun albeit a little claustrophobic. Really enjoyed the camel ride around the Giza plateau - great fun.

DB Cooper is completely right about getting harassed by merchants at all of the tourist sites. There is a "market" at the entrance of every single historic site that we referred to as "the gauntlet" where you had to dodge increasingly aggressive touts trying to sell you just about everything under the sun.

The river trip from Aswan to Luxor was amazing. Got to visit the Valley of the Kings, Karnak Temple, Aswan High Dam, among other temples/sites.

I strongly recommend tour groups with preplanned transportation just due to how difficult it is to get around the area.

I hope that the cellular infrastructure in Cairo is good enough to make Uber useful. I had a lot of problems staying connected when I was in Mexico City, such that I consistently had problems meeting up with drivers. And my cell reception in CDMX was pretty good in comparison to some other places I've been (see: most of Canada).

I was just in Rome and Google Fi was spotty at times.

Except maybe for going out to dinner, it would be foolish not to use a private guide and driver in Cairo for two days of sightseeing. The Antiquities Museum at Tahrir Square is overwhelming without a guide.