Connect the LAN of 2 Router to share files and resources

Hello guys,
I’ve two Mikrotik RB1000 Routers (R1 & R2) connected to 2 gateways with internet access. R1 is connected to a gateway which provides internet to office-A with 50 computers and R2 is connected to another gateway which provides internet to office-B with 40 computers.

I want the computers in Offices A & B to “see” each other so that they can share files and resources but still be connected to their own routers and gateways.

Please, someone help.

create tunnel between the routers and set up static routing so both networks are reachable through the tunnel.

pptp or l2tp should suffice.

Note that in order to have resource browsing (you open Explorer and the shares just show up) you’ll need either a domain, or a WINS server. Without them, only shares on the local broadcast domain will show up.

I already I hv a domain server implemented within the network…now do u advise i add every PC & and Resource i wish shared to this domain?