From the 5 locations proposed as Oil Heritage, only the Trans Arab Tapline is accessible. 

Well 7, KFUPM and Dhahran Camp are all within the Saudi Aramco Campus in Damman and the guards would not let us in. Only if you work there or get an invitation by someone who works and lives on the campus you get access. 

The Jeddah Refinery is part of the Luberef Oil Refinery campus. Access for employees only.

The only “visible” component is the Tapline. It runs mostly underground along the Tapline Road from Damman to Jordan, but becomes partially visible from around 20km along the Tapline Road after the junction to the airport. Unfortunately, when planning a visit I did not focus on the pipeline (I really counted on the Well no7) and only saw that on the map back home.