Because my sister said it goes straight off the bridge and you have to fly to go to them...Yer siblin' is correct in that statement. The portals do go right off the edge of the bridge and keeps on goin' and if a portal ye' wish to reach is included in those that continued from said bridge, ye' will have to equip wings to reach it. However it doesn't stop at the invisible force field that surrounds each map. Even then, the portals will keep goin' but ye' will be unable to reach 'em. When that happens, the only thing ye' can do is delete some of the maps ye've downloaded to shorten the line length.