ok i found out that there really IS A 4 ISLAND IN gta3! WANNA KNOW HOW TO GET TO IT?? all u have to do is beat the entire game= ALL MISSIONS, ALL HIDDEN PACKAGES, ALL SIDE MISSIONS , AND EVERYTHING ELSE! when u do that, then go to the dam in SHORESIDE VALE and on the right side is a tunnel. that should lead you to a new island called CARSER CITY! u can also hear about this island on the radio sometimes. in Carser City there is a garage WITH UNLIMITED CAR SPACE and the WHITE HOUSE where the president tells u to kill Kenneth Star. Carser City has A LOT of MR. Whoopees and EVERY SINGLE CAR just driving around. like the FBI cars and Swat team cars and every other cars, including some new ones too!

 

Now this source is not confirmed.....so dont get your hopes up.