Random thoughts as they spill out.
When I was there last year almost everything I went to take pictures of had scaffold over it.
That said, they are still great things to go and see. It is the remnants of the Roman Empire after all.
The Colosseum and Forum should be able to be seen on the same ticket. It usually lasts for 2 days, so on the 1st day, and the other on the 2nd. I wouldn't try to do them in the same day, especially with a child. On my first visit to the Forum I thought I saw it all, but went again last year and realised I'd only seen half of it.
Love the Pantheon. It is my favourite building in the World. And it's free too.
I go there a couple of times during a trip to try and the 'the' pic to show it off to its best. I haven't got that pic yet.
Trevi Fountain is worth a visit, whether there is building work there or not, just to marvel at what they built, and where they built it.
A few lovely places to get Ice-cream there, with so many flavours to choose from. I think I had a Mint, Lemon, Mango and Strawberry combo there once. I hardly ever get hassled by street vendors, but a polite but firm 'No Grazie', is enough to get the message across.
I usually get a travel pass when I'm in any large city, as whilst it is easy to walk around Rome in this case, being stuck on the opposite side of the city to where you are staying makes the walk back feel 10x as long at the end of a hot day. I found the buses in Rome quite reliable and frequent.
Pick up some maps at the airport, or go to one of the Tourist Information Centres as soon as you can in the city to pick up maps and guides. It is a very easy city to lose your bearings in, as it is built around a twisty river. If you have an Android device with GPS, or even if it hasn't got GPS, I've found a great downloadable (free) offline map called OsmAnd. I haven't used it abroad yet, but it work great here.
Castel Sant'Angelo is interesting for the design of it inside, and you get a nice view of St Peter's from the top. And that area of the city is nice around sunset for view along the river again to St Peter's. A clichéd view maybe, but doesn't make it any the less beautiful.
I found Ostia Antica very good, but there is not much shade there. Scorchio in the July I visited there.
The Vatican Museum has lots to see, but get there early if your ticket allows it. If no one is averse to heights, there are great views over the city from the dome of St Peter's, but get there as soon as it opens. I got there just before 9am and waited 5-10 minutes to go up to the top of the Dome.
If you climb the entire 551 steps the admission cost is 6 Euros; if you take the lift as far as the terrace and climb the remaining 320 steps the cost will be 7 Euros.
Pay the extra to get the lift to the base of the Dome. It is still a climb to the top, but it is worth it imho. Whilst I was up there the queue had grown half way around the square. After I had come down, looked around the Basilica, the queue was looping back on itself, 360 degrees 3-4 people deep.
Get there early.
If museum visits are your thing, the Museum of Roman Civilisation in the EUR part of the city is worth a visit. They have amongst many fine things, a massive scale model of Ancient Rome, and a cast of Trajan's Column from the centre of the city. The detail, which is hard to see in situ, is unbelievable close up.
Also in the EUR part of the city is the The Palazzo della Civiltà Italiana, also known as the Palazzo della Civiltà del Lavoro or simply the Colosseo Quadrato (
Square Colosseum), is an icon of Fascist Architecture, but beautiful none the less. Best seen on a weekend when there surrounding offices are empty, and there are not many cars parked in front.
On my visit the year before last I went on a Segway tour of the City which I saw things I had never seen on the previous 3 visits. It's a great way to see the city. Unfortunately it's for 16+ only, but I advise anyone to have a go if they get the chance.
I try to holiday on the cheap, so my budget is about €20 a day.
I get a couple of bottles of Coke in the airport, pre flight. I go to a local super market to get some 1.5lt bottles of Coke, and two of those bottles in a supermarket are normally close to the price of 500ml bottle of Coke from a street vendor. I use those bottles from the flight filled each morning with Coke. And then during the day I fill those bottles with water from the many fountains around the city. Drink all the time, especially in that heat, and keep the little one hydrated.
If you want a chill out day, a visit to the park around the Villa Borghese is a respite from the Sun, lots of trees and seats,
and has lots of bikes and buggies, pedal and electric, to go look around the Park. It is quite busy on the weekend though as the locals flood the park. There's even a little boating lake.
Of course what you can and can't do will be dictated to large degree by the child you have with you, especially in that heat. It is their holiday too after all.
Woah, that's a lot. Hope you find something useful in all that.