PHILADELPHIA (CBS) – Whether you’re new to Philadelphia or grew up here, it’s probably safe to say you haven’t seen the city like this.

On Saturday, Sept. 8, the Association of Philadelphia Tour Guides (APT) is hosting the third annual “Great Twelve-Hour, River to River, Vine to Pine, Rain or Shine Tour” of the city.

And while most tours similarly cover historical sites, attractions, museums and other points of interest, this tour covers 200 of them—in a single day!

The lengthy trek through the city is actually split up into four phases with separate launch sites where participants can sign in and get started, and tour-goers can start the journey at any point.

APT says that nearly 400 people from the area and some out-of-towners have participated in the last two tours, and that each year, several people have made it all the way through the entire tour.

The four tour launch sites and times are: 8 a.m. at the National Constitution Center; 11 a.m. at The Bourse at 5th St.; 2 p.m. at the Independence Visitors Center; 5 p.m. at City Hall Courtyard.

For more information, visit: www.phillyguides.org/greattour2012.aspx