Yes, visitors are allowed to walk inside Machu Picchu, but there are some restrictions to protect the historical site. Visitors are required to stay on designated paths and are not allowed to climb on the ruins or touch the stonework. Additionally, visitors are not allowed to bring food or drinks inside the site, with the exception of water in a clear plastic container.

There are several walking routes inside Machu Picchu, ranging from easy to moderate difficulty. The most popular route is the Classic Inca Trail, a four-day trek that covers 26 miles and passes through several archaeological sites before reaching Machu Picchu. However, for visitors who prefer a shorter and less strenuous experience, there are also shorter walking routes available, including the Huayna Picchu and Machu Picchu Mountains.

Overall, walking inside Machu Picchu is a unique and unforgettable experience, offering visitors the opportunity to immerse themselves in the rich history and culture of the ancient Inca civilization.