Perhaps you are traveling to Rome and only have a couple of days to wander around. Perhaps you don’t want to rush, plan too much, and stand in too many lines.
Here is one walk that is relaxed and very easy to accomplish in one day, an evening if you don’t go inside the Pantheon [go inside the Pantheon though, really].
Take a hotel room on Via Veneto. Walk to Via Vittorio Veneto past the Hard Rock cafe and down to Piazza Barberini — where you will see a beautiful, but smallish by Roman standards, fountain, Fontana del Tritone.
Wind your way to Via Sistina, just the street further off the front of the fountain. Turn towards a tall Obelisk, Via Sistina and walk through the charming street, along with 57 other people to see the view, the Roman-made obelisk, the beautiful church. If you head towards the other Obelisk, you will be on Via delle Quattro Fontane which goes up a hill, then you see an intersection with a small fountain on each corner. Head back the other way.
Next, walk into the beautiful church. Then after you say a prayer for world peace, head back to the view, then down the Spanish Steps and see the fountain at the base, look up in awe at the steps themselves. When it is raining, you might have most of the steps to yourself, except for those guys who sell umbrellas, self sticks, etc.
Once you have taken lots of pictures of yourself near the fountain — be sure you don’t get into the fountain, the police will blow whistles at you and admonish you in Italian. Continue forward [West] on Via dei Condotti past several luxury shops and when you get to the Fendi flagship store, look around for another column — this one is an intricately carved memorial to Marco Aurelio [Marcus Aurelius] commemorating his victories. Continue on around the bend to see another obelisk, Obelisk of Montecitorio. Then wind your way around — following the crowd to the Pantheon, where there is another fountain, a Salumeria, and restaurants with outdoor seating.
Enjoy the Pantheon, then take a side street back, winding past the Trevi Fountain, then back up to Barberini then up to Via Veneto. Use Maps to ease some of your anxiety about getting to Trevi fountain, although most likely, you will follow the crowd past Hadrian’s columns from his temple, Il Tempio di Adriano in the Piazza di Pietra …
and right over to Fontana di Trevi [Trevi Fountain of movie fame]. The scene over at Trevi fountain is amazing and there is a lot of police whistles going on to keep the crowd under control. Trevi is beautiful by day and beautifully lit by night, and worth seeing under both conditions.