At its maximum extent , it is about NUMBER@1 km -LRB- NUMBER@2 miles -RRB- long , and NUMBER@3 km -LRB- NUMBER@4 miles -RRB- wide .

At its biggest extent , it is about NUMBER@1 km -LRB- NUMBER@2 miles -RRB- long , and NUMBER@3 km -LRB- NUMBER@4 miles -RRB- wide .
