As I enter the Roman Forum just a 2 min walk from Colosseum I felt transported back to history. Its a humbling experience to walk down the awe inspiring ruins as it makes one realise that nothing is permanent in life. Even the most powerful empire lay in ruins!!
Many people avoid Roman Forum as there quite a bit walking to be done. The time required is atleast an hour and a half. Many people have an aerial view and leave. I would suggest you walk down and past the monumental remains that was once a part of glorious history. You will be touched by its sheer beauty; magnificence and architectural brilliance of what ever is left.
Hire a guide or take an audio guide.Its MAGIC!!

The first time I visited about 7 years ago, there was no charge to enter the Forum. But charge or not this is a place not to be missed. Firstly, it is very important to know a little of what you are visiting so a good guide book is indispensable. How about the eyewitness guide to Rome for starters. Why not read something of ancient Roman history before you go. Read about Romulus and Remus, about the Caesars, Julius, Augustus and Nero. Think about the intrigues, the poisonings and murders that happened around and in these ancient ruins, the place where Julius Caesar stood to address the crowds and where he was stabbed to death. The site of the Roman sennet. Go to the site of Augustus's house and look down into the great palaces and gardens where so much brutal and intriguing history happened. Gaze at the triumphal arches of Titus and Septimius Severus and read of their place in Roman history and imagine the cohorts of soldiers marching through them. Imagine the orators standing on the rostra begging the Romans to lend them their ears. Walk around the temple of Julius Caesar that marks the place of his cremation and wonder at the exploits of that great man. And after that there is still the house of the vestal virgins, the temple of Antonius and Faustina and much much more to consider. Fantastic, what a day out.

there are no writen signs anywhere... If you don't have guide book, ther no reasen to go.
My suggest take guided tour, or don't go

We visited the Roman Forum after touring the Colosseum. We didn't see nearly everything we'd like to see and plan a return visit to continue our tour. Ruins are not well marked so recommend an audio guide to use with the map of the site to allow you to move at your own pace. There's plenty of places to sit and enjoy the atmosphere and take in the georgeous views. Lots of people so be prepared, even in late September!