Obelisks at Red Hill Peninsula and Obelisk Hill

The obelisk at the Red Hill peninsula ( lower left of photo ) appears to match the other obelisk at the top of the Obelisk Hill ( near Shek O Road) .

I am interested in any information regarding the pair of obelisks:

1 Year built 

2 By whom

3 Purpose

4 Are they declared ancient monuments 

5 Any other details 

Best wishes! 
 

Paul Tsang 

6 January 2021