When it comes to planning my travels, I'm a huge proponent of buying admission tickets directly as it cuts out any problems related to third-party businesses. There are exceptions to this rule; in the case of buying Colosseum tickets, the process to buy said tickets on the official coopculture.it site is a TOTAL NIGHTMARE. If you want to try your luck at booking yourself, check dbabe's posts on the TripAdvisor Rome forums - she tells you step-by-step how to do this.
For the people that don't want to go through the hoopla, there are plenty of choices when it comes to third-party tours of the Colosseum. The most obvious choices are Walks of Italy and City Wonders/Dark Rome (which also offers Vatican tours if you're so inclined) but you have to take into consideration that the Colosseum doesn't just consist of the ground floor. The coopculture.it site lists the regular tour (1st and 2nd levels with arena floor), the underground, "panoramic view" (aka the belvedere - 4th and 5th tiers) and both. During my research, it turns out that the all-in-one tickets sell out *fast* through official channels because third-party has to go through the same process to buy tickets. Furthermore, several third-party companies offer the underground and/or belvedere tour but only ONE company managed to offer both on the same itinerary. Guess which company got my business.
Here's the URL to buy tickets for the all-in-one-tour (https://www.romaexperience.com/rome-tours/all-in-one-colosseum-tour/). Includes skip-the-line privilege.
Cost: €129.00
Length: 4 hours
Includes: Colosseum/Underground/Belvedere, plus Roman Forum and Palatine Hill.
Meeting Point: directly across from the Colosseum.
(Conversely coopculture.it costs €29.00 for just the Colosseum/Underground/Belvedere, but good luck getting tickets...)
The first part consists of the Colosseum tour, which is given by the official coopculture.it guides. There is no way around this. For this portion of the tour you are also combined with another group so max ~24 people. She did her best with explaining all the levels but it was hard to understand her at times especially with her thick accent!
The rest of the tour consist of the Forum and Palatine Hill. They are normally included in the cost of your Colosseum ticket and said ticket is valid for a 48-hour period, but there's no included guided tour nor audioguide. A good guide is essential to make the ruins "come to life", especially if you didn't do prior research or history/archaeology isn't your interest. While I was able to pay attention to the Colosseum portion of the tour, it was hard to pay attention towards the end. Didn't help that it got hot (37C); she rushed the Forum portion of the tour because people were more concerned about getting shade so I wasn't able to retain much information.
I would still recommend this tour as a way to fully experience the Colosseum especially if you want to visit all the areas as only this tour lets you visit all the floors. I just wish that the guides that gave the tour were a bit more engaging so that I could learn more about these sights.
PS: If you have at least two full days in Rome, it is strongly recommend to make your Vatican and Colosseum visits on separate days to maximize your sightseeing. They do have a combo Colosseum/Vatican tour but due to the nature of the site this would be one long, grueling day. read more