Anne's Beach or Coco Plum Beach: the Florida Keys Verdict
Published 2026-09-06. Conditions described are typical and never guaranteed.
The short answer
These are two quiet, free, very shallow natural shores, and neither is a proper swimming beach, so the choice comes down to who you are travelling with and what you want from an hour by the water. Pick Anne's Beach if you have small children, you are already driving through Islamorada, and you want a shaded picnic beside a mangrove boardwalk with somewhere gentle to wade. Pick Coco Plum Beach if you are travelling with a dog, you love a slow shelling walk, or the idea of a roped off turtle nest fascinates you more than a groomed strip of sand ever could.
Both sit on the Atlantic side of the chain, both are free, both give you a covered pavilion and restrooms and not much else, and both read as paddling and picnic shores rather than places for a long swim. If your heart is set on getting fully in the water, neither is your beach, and I will point you to the one that is further down.
Anne's Beach is the easy family wade in Islamorada. Coco Plum is the dog and shelling beach in Marathon. That single line settles most decisions.
Where they sit on the drive
Geography does a lot of the deciding here. Anne's Beach is at mile marker 73.5 on Lower Matecumbe Key, in the Islamorada stretch of the Upper Keys. If your day already runs through Islamorada, it is a natural roadside pause. Coco Plum sits near mile marker 54 on the Atlantic side of Marathon, roughly twenty miles further southwest. That gap matters more than it looks, because you rarely reroute your whole day just to swap one shallow beach for another. Whichever town you are staying in or passing through usually wins the toss before conditions ever come into it.
If you want the wider picture of how these fit into the region, the overview of the island chain lays out the drive from Key Largo down, and the seasonal guide is worth a look before you fix a date, because both beaches are calmest and clearest in the dry winter months.
Sand, water and the feel underfoot
Neither of these is a wide postcard beach, and it helps to say so plainly. Anne's Beach is a narrow natural sand shoreline edged by mangroves, modest in size, with a coastal forest sitting behind it rather than open dunes. It is intimate and green, not sweeping. The water is the standout feature: warm, very shallow flats that stay gentle a long way out, which is exactly why parents with toddlers love it. There is grass and soft mud in places, so water shoes earn their keep.
Coco Plum trades in a slightly different texture. Its sand is a coarser natural strip mixed with seagrass and shells, wild and quiet rather than groomed. The Atlantic shallows here recede a long way at low tide over a soft seagrass bottom, which is what makes it such a rewarding shelling beach and such a frustrating one if you turn up expecting to swim. The tide dictates your visit. Come toward higher water if you want to get in at all, and treat the calm as typical rather than promised, since there is no lifeguard to rely on at either beach.
So the honest read on the water is this: both are wade beaches. Anne's stays shallow and consistent, which suits little legs. Coco Plum swings with the tide, which suits patient beachcombers who plan around it. If you are choosing on the water alone, Anne's is the safer bet for a spontaneous stop, and Coco Plum rewards those willing to check the tide chart first.
Facilities and crowd
Do not come to either expecting sunbeds, a bar or gear rental. What Anne's Beach offers is a long boardwalk through the mangroves that links its two small roadside parking lots, with several covered picnic pavilions and restrooms along the way. It is genuinely lovely to walk, and the shade of the coastal forest is a real asset in high sun. There are no shops, no food and no rentals on site, so you carry in your own water, food and shade or you go without.
Coco Plum keeps things equally simple: a covered pavilion, restrooms and a parking area, run by the City of Marathon, typically open from around 7:30 in the morning until dusk, though hours are best confirmed locally. It is low key and quiet, the kind of place where you might have long stretches of shore to yourself outside the winter peak.
On crowds, both fill fastest in the December to May window, when the water is clearest and the seaweed least. Anne's has only two small lots, so parking is the real pinch point on a busy dry season day, and arriving earlier is the single most useful move. Coco Plum tends to feel the more solitary of the two by nature, part of why it appeals to people chasing quiet. If seclusion is your priority above all, the quiet shores roundup is worth a browse alongside this one.
The two things that flip the decision
You are travelling with a dog
This is the clearest tie breaker of all. Coco Plum is one of the few beaches in the Florida Keys where dogs are officially welcome, kept on a leash and cleaned up after. Most beaches in the chain do not allow them at all, which makes this stretch a genuine find for anyone road tripping with a dog. Anne's Beach makes no such offer. If there is a dog in the car, the decision is made for you: Coco Plum wins, and it is not close. Do check the current city rules before you go, as access can change through the year.
Turtle nesting season is on
Coco Plum is a known sea turtle nesting beach, and from mid April to the end of October parts of the sand may be roped off to protect the eggs. You will not be guaranteed to see a turtle, since nesting happens after dark and nests are protected, but the marked nests and the wild setting make it a quietly special place to walk in those months. For some travellers that is the whole reason to choose it. For others, roped off sections and a beach in its wilder, weedier warm season state are a reason to go elsewhere, and in that case Anne's, with its consistent shallow wade, becomes the easier family day.
So which one, honestly
For a family with young children who want to splash safely and eat lunch in the shade, Anne's Beach is the pick. The mangrove boardwalk, the pavilions and the reliably gentle shallows make it one of the best free stops on the Islamorada drive, and it does its modest job beautifully. Keep a close watch on children in the water regardless, because the calm is typical rather than promised and there is no lifeguard to depend on.
For dog owners, shell hunters and anyone drawn to a wild, low key shore with a turtle nesting story, Coco Plum is the more rewarding stretch, as long as you time your visit toward higher tide and accept it as a paddling beach rather than a swim.
And if what you really want is to swim, be honest with yourself and skip both. The one true wide natural swimming beach in the chain is Bahia Honda State Park at mile marker 37, with soft sand across three beaches and clearer turquoise water than either of these can offer. There is a modest state park fee and the gate can close when the park fills, so arrive early. I have set that beach against Anne's directly in a separate head to head on the two Islamorada options if that is the comparison you actually need. Families weighing up a full day of facilities may also want to read the family beach guide before committing.
Plan a beach club day in the Florida Keys
Anne's Beach and Coco Plum are free public shores with no loungers, service or dining on the sand, so if you would rather pair your beach time with a day bed, a pool or a proper lunch, that is a different kind of day out. Browse the options on our Florida Keys beach club page to see what is available and to enquire about booking a club day that suits your group.