Transit question
 

I am travelling from hkg-lhr via CX and connecting on a BA flight to Barcelona next week. I don't travel that much and need any information I can get such as immigration clearance and baggage transfer.

P.S. I will be staying in Le Meridien hotel in Barcelona. ARe there any must-see places as a tourist?

Thanks

You arrive at LHR3 on CX and need to make your way to LHR2 (or is it 1?). Go to flight connections if you want to avoid going through immigration and customs (just make sure the HKG staff check your luggage through to BCN).

So is there a need to clear London customs?

BA flights for BCN depart LHR T 1.

You don't need to clear customs and immigration. You tag your baggage all the way from HKG to BCN.

You go to T3 connections centre, and take a bus to T1 for your connection.