Mike, We have left Marathon late afternoon, crossed to South Riding Rock then across the banks. There are really no
anchorages unless you go up to Key Biscayne and cross over to Cat Cay leaving just before daybreak. Depending on the speed of your
boat you can
anchor in Honeymoon Harbor near Cat and cross the banks to maybe Chub the next day. There is also a marina at Cat Cay that you can stay and also check in. You can
anchor on the banks but you really want settled
weather. At least 2 and preferably 3 day good
weather window is desirable.