UK Resident Dubai - Hong Kong - Beijing - Indonesia

Hello,

I am a UK resident that will be travelling this summer. I will be travelling from Dubai to Hong Kong (72 hours in Hong Kong), Hong Kong to Beijing (2 and a half days in Beijing) then flying to Indonesia.

Am I eligible for a 72 hour free transit visa?
Would I be allowed to visit the Muthianyu section of the great Wall?

Thanks
Emily