There is a viewing platform at the base of the lantern from where you can enjoy an unparalleled panorama over Rome. You have the option of taking the elevator or the stairs, the latter being a bit cheaper.
At the foot of the dome you can walk onto the roof terrace, from where you get a close-up view of the dome. The galleries inside give you a birds-eye view of the interior of the church. From here a long, narrow and spiralling staircase brings you to the top of the dome.
The staircase is situated between the inner and outer shells of the dome, so the walls are somewhat slanted. The rather uneasy climb (and entrance fee) are definitely worth it though since you are rewarded with one of the best views over the city.
You can click on the following image to see a larger version of the panorama.
Please feel free to use my images under the Creative Commons Non-Commerical Licence.
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