Great Island is a pine tree and green brier covered hummock in the extensive Sandwich Harbor Marshes Conservation Area located behind the barrier beach at the east end of the Cape Cod Canal. A low narrow causeway leads out to the hammock which can be cut off from land at extreme Spring tides. The whole area is open to exploration by kayak or small boat but the ten foot tides in the area greatly affect navigation. The D/T rating is based on arriving at low; it will play harder at higher tides: you can check the predictions here: Tides
(See the Related Web Page for additional information about the area.)
This a a five stage multi, about a mile and a half round trip. The stages are constructed with local "found objects" and at least one marker is off the ground at each stage location. There are both hard and easy ways to get to each, so think about your route as you go along. Direct routes are possible but will be very thorny
edexter
F1: yrsg fvqr fghagrq bnx; evtug fvqr ab onex (2)
F2: cvar: gur svfu tbg njnl
F3: rireterra: gur genc tbg ybfg
F4: anxrq naq ybaryl
Pnpur: rlr uvtu