there is this kind of buses in Beijing and here are the routes of them:

You 1: Qianmen- Badaling Great Wall- Dingling (one of the Ming Tombs)- Changling (one of the Ming Tombs)- Jiulong Amusement Park Fee: 9-11RMB
You 2: Beijing Station- Badaling Great Wall- Juyongguan Great Wall- Dingling- Changling- Jiulong Amusement Park Fee: 9-11RMB
You 3: Dongda Bridge- Badaling Great Wall- Juyongguan Great Wal- Dingling- Changling Fee: 9-11RMB
You 4: Zoo- Badaling Great Wall- Juyongguan Great Wall- Dingling Fee:9-11RMB
You 4: Xizhimen- Badaling Great Wall- Juyongguan Great Wall- Dingling Fee: 11RMB
You 5: Qianmenxi- Badaling Great Wall- Juyonggua Great Wall- Dingling- Changling- Jiulong Amusement Park Fee: 9-17RMB
You 6: Xuanwumen- Mutianyu Great Wall- Hongluo Temple- the lake:Yanqi Hu Fee: 24RMB
You 6: Dongsishitiao- Mu Mutianyu Great Wall- Hongluo Temple- the lake:Yanqi Hu Fee: 24RMB
You 7: Qianmen- Tanzhe Temple- the cave: Shihua Dong- Jietai Temple Fee: 22RMB
You 7: Fuchengmen- Longqing Gorge-Badaling Great Wall Fee: 32RMB
You 8: Qianmen- Longqing Gorge- Badaling Great Wall Fee: 32RMB
You 8: Andingmen- Longqing Gorge- Badaling Great Wall Fee: 32RMB
You 9: Ming Emperors Wax Museum- Dingling- Shisanling Reservoir- Mangshan Park- Jiulong Amusement Park
You 9: Zoo- Ming Emperors Wax Museum- Dingling- Shisanling Reservoir- Mangshan Park- Jiulong Amusement Park
You 9: Xuanwumen- Ming Emperors Wax Museum- Dingling- Shisanling Reservoir- Mangshan Park- Jiulong Amusement Park Fee: 24RMB
You 10: Fuchengmen- Yuju Temple- Shidu Fee: 20RMB
You 10: Qianmen- Yuju Temple- Shidu Fee: 20RMB
You 12: Xuanwumen- White Dragon Pond (Bailong Tan)- Simatai Great Wall Fee: 25RMB
You 12: Dongsishitiao- White Dragon Pond (Bailong Tan)- Simatai Great Wall Fee: 25RMB
You 14: Exhibition Hall- Jinhaihu Park Fee: 22RMB
You 14: Dongda Bridge- Jinhaihu Park Fee: 22RMB
You 16: Xuanwumen- Hongluo Temple- Qinglong Gorge Fee: 16RMB
You 16: Dongda Bridge- Hongluo Temple- Qinglong Gorge Fee: 16RMB
You 18: Xuanwumen- Panshan Fee: 27 RMB
There are also Sight Seeing Trains to near cities running lines are as the following:
From Beijing Station (8 lines)
Y209 Beijing (7:52)- Fengren (9:29)- Beidaihe (11:01)- Qinhuangdao (11:32)
Y201 Beijing (7:18)- Beidaihe (9:48)- Qinhuangdao (10:21)
Y211 Beijing (8:35)- Tianjingbei (10:08)- Tianjing (10:25)
Y213 Beijing (10:20)- Tianjingbei (11:49)- Tianjing (12:02)
Y215 Beijing (15:45)- Tianjingbei (17:15)- Tianjing (17:28)
Y211 Beijing (19:09)- Tianjingbei (20:38)- Tianjing (20:51)
Y219 Beijing (21:18)- Baijian (23:45)- Lingqiu (2:38)- Wutaishan (4:06)- Yuanping (5:40)- Xinzhou (6:21)- Taiyuan (8:00)
Y225 Beijing (7:29)- Huairou (8:31)- Xinglong (10:12)- Chengde (12:10)