This tour was truly amazing. Took part in it on a rainy, foggy day by the lead of a fantastic, professional personal Guide (Lee) and a kind Driver.
At first, I can recommmend Novotel Hotel at Sanyuanqiao (can be located with ease by Airport Express - as a starting point and the staff was really helpful (despite I was not their Guest, treated me like that) when wanted to call my contacts, also gave free Wifi, etc.
The way to and from the Wall was awesome. I was just listening to whole China's history (Lee was prepared! :D), the establishment of different areas, the kingdoms, about the main purpose of the Wall, etc. Also had the chance to take a glimpse onto the the Bird's Nest (Olympic Stadium, Opening Ceremony Point of the 2008 one), despite it was not in the original program. Full generosity.
The Wall appeared as a romantic spot, was a real adventure to climb up to the top on the slippery stairs and look around on this top quality, world heritage site.
After the ~1,5-2h walkaround, got back to the city just before time and could catch my plane without any worries.
Can not say other than the service was 1st class and you should not miss this organization when you meet with some of the same opportunities as me.
——from Viator