Description :  We are now halfway up the entrance walkway and the Sun continues to bathe our head (glad we used all that suntan lotion). Are those girls  twins? They appear twice in the panorama...why? Looking at the "nadir" (your feet) you will see a manhole cover of the (not-coloinal) sanitary system. To the north, the green manhole box is the storm sewer system. Both run parallel to the access walkway.

More information can be found at the National Park Service Site.