Four small planets lie quite close to the Sun. All of them have about the same density as the Earth and so they are called "Terrestrial". Besides the Earth, they are Mercury, Venus, and Mars. The most distant of these planets from the Sun is Mars, a little over 1.5 A.U. from the Sun. Want to walk about 350 million miles? Then head for the next nearest planet: Jupiter.
As you cross the road on your way to Jupiter, watch out for vehicle traffic! If you were crossing between the orbits of Mars and Jupiter in the actual Solar System, you would have to watch out for asteroids. They are found in great numbers in this region of the Solar System (they appear on the Solar System Map of the Inner Planets as Ida and Gaspra) near the giant planet Jupiter. It's the largest planet in our Solar System and its strong gravitational tug probably broke up a small planet that came too close.
As you walk along the path from the model of Neptune to the model of Pluto, you are following the orbital path of Neptune as it circles the Sun - but in the opposite direction to the real motion of the planet. It would take Neptune about 20.5 years to make the trip you will complete in about 3.5 minutes!
Pluto is about 1600 feet, in a direct line, from the corner of Albertus Hall - where our solar walk began. The real Pluto is nearly 4 billion miles from the Sun! Our walk from the Sun to Pluto took about 15 minutes: light from the Sun, traveling at 186,000 miles per second, would take about 5.5 hours to reach Pluto.