Mile Markers (MM) are a relative location of a site in reference to the number of miles north of Key West.  The business center of unincorporated Key Largo is at about MM 100; therefore, about 100 miles northeast of Key West.  The Florida DOT tries to maintain small rectangular green with white number mile marker signs every mile on both sides of the highway.  Generally except Marathon, addresses along the highway is the MM expressed as a four, five or six digit number.  For example, a business with an address of 100511 Overseas Highway would located at about MM 100.5.  If the extreme right digit (least significant) number is an even number, it is on the west or Bay/Gulf side.  If an odd number it is on the east of ocean side.  Subtracting two MM's gives the approximate number of miles between two known locations.  If the MM's are getting smaller, one is traveling south or southwest. These are listed from north to south. Note: the farther south in the Keys one is, the more east and west the highway runs.  Business/commercial location may change or even disappear.  I assume this practice began with Henry Flagler who numbered every mile of railroad beginning at Jacksonville and ending at Key West. They were white and black concrete Mile Post signs along the railroad track and on the printed timetables.  This list of MM's are approximate as I have recorded them.

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127.5 = Florida City - Junction with Fla. Turnpike and U.S.1

126.5 = Junction U.S. 1 with CR-905 to/from Card Sound Bridge and Ocean Reef Club, Oceanside. Also an alternate route,  $1.00 bridge toll, if southboun

126.0 = End/Begin two-lane "18 Mile Stretch." If southbound, please drive carefully. 

123.5 = Florida Sand and Gravel site, oceanside 

123.0 = Dade Correctional Institution, gulfside 

118.0 to 121.0 = Four-lane passing zone 

119.5 = Dirt road turn-off, gulfside 

116.3 = C-111 Aerojet canal bridge  

114.1 = to 116.0 Four-lane passing area

114.0 = South Dade Marina & boat storage, Oceanside 

112.5 = MONROE COUNTY LINE - Leave Dade County if southbound. 

110.8 = FKAA Water Pump Station, Oceanside. Little Black Water Sound Boat Ramp, gulfside 

109.3 = Osprey bird nest, Oceanside 

108.0 = Osprey nest, Oceanside

107.2 = Jewfish Creek drawbridge. Exit/enter Key Largo. Begin "18-Mile Stretch." If northbound, please drive carefully.

106.6 = Lake Surprise  

106.5 = Card Sound Bridge turnoff to/from Ocean Reef via CR 905 Oceanside. Also an alternate route, $1.00 bridge toll, northbound to Homestead.

If taking CR905, the following MM's apply and are labeled "C". At C-5 soundside is the solid waste transfer facility. At C-7 oceanside is the former Carysfort Campground. At C-7.5 soundside was the former Nike missile launch site. At C-8.5 oceanside is the remains of the Nike missile radar site. At C-9.25 is a three way stop. Straight goes to the Anglers and Ocean Reef Clubs gated communities. Left goes across the Cardsound toll bridge to Homestead. At C-11 to the left is the Angler's Club and straight ahead is the Ocean Reef Club. Now back to MM's.

106.0 = Key Largo Chamber of Commerce, gulfside;  FKEC Power sub-station oceanside 

105.9 = County Animal shelter, oceanside 

105.6 = The location of the railroad depot and the center of the community of Key Largo from about 1910 to 1940.  The depot was in the highway median.  The community was gulfside

105.5 = St. Justin Catholic Church, gulfside 

105.4 = Winn-Dixie Shopping Center, gulfside 

105.3 = Stillwright Point community entrance, gulfside 

105.0 = Cracked Conch Restaurant, oceanside 

104.8 = Key Largo Elem. School, oceanside  

104.5 = Taylor Creek Village, oceanside; Tamarind Park, gulfside  

104.1 = Caribbean Club, gulfside. The set for the 1948 moive Key Largo was modeled for this location. 

104.0 = Italian Fisherman Restaurant, gulfside 

103.5 = The 1920s Key Largo Rock Castle, End of Oceana Drive, Oceanside

103.4 = Marvin Adams Waterway Bridge (The Cut), a canal that connects Atlantic to Florida Bay 

103.8 = Central (Pink) Plaza Shop Center, gulfside 

102.8 = John Pennekamp State Park entrance, oceanside  

102.2 = Kli/Shell Lumber & Hardware, oceanside

102.2 = Arthurs Island Kitchen. Floribbean Cuisine , oceanside

102.2 = VFW Post 10211, ocean side

102.0 = Telephone microwave towers, gulfside 

101.5 = Tarpon Basin Road, Key Largo Library, Tradewinds Shopping center, oceanside 

101.2 = Hibiscus Park, Oceanside. The was the center of the 1880s community of Newport. 

101.0 = Calusa Trailer Park, gulfside 

99.8 = Key Largo Post Office- ZIP 33037, gulfside 

99.5 = Waldorf Plaza,  oceanside. 

98.0 = Landings of Largo, gulfside

98.8 = Moose Lodge # 2287 - Live Music, Wednesday Nights 7 - 9 PM "Key Largo Woodrats" · Tim Dressing, median

            Everglades Park Ranger Station, gulfside. 

1st Baptist Church, oceanside; Shell World (center road); Rock Harbor Club, gulfside 

95 to 100 = This was the early community of Rock Harbor. A small railroad depot was also here. 

97.0 = Westin Hotel, gulfside 

96.0 = Silver Shores community, oceanside; Winken Blinkin and Nod Estates, oceanside. Buttonwood Bay gulfside  

95.3 = Key Largo Ocean Resorts, oceanside. Key Largo Prof. Center., gulfside

95.2 = Florida Keys National Marine Sanctuary building. 

94.8 = Seaside community, oceanside. The 1900s Thompson line packing house was in this area.  

94.0 = Red Cross Center, gulfside; Glander Boats oceanside, Sunset Hammock, gulfside. 

93.8 = Wild Bird Center, gulfside 

93.1 = Hammer Point community, WFKZ Radio tower and offices, gulfside

92.9 = Jewish Center, oceanside 

92.8 = Burton Memorial United  Methodist Church, oceanside 

92.6 = Burton Drive, Harry Harris Park oceanside. The early community of Planter included the park area, but the community center was about 1,000 feet south. 

92.2 BPOE Lodge, Bank of America, gulfside; Driftwood Trailer Park, oceanside 

91.9 Old Tavernier Post office; Old Settlers Park, oceanside Tavernier Hotel, oceanside. This was the center of the early community of Tavernier. Its depot was in the median just south of the post office. 

91.8 = Reporter Newspaper; FKEC Power Station, Oceanside; FKAA, gulfside  

91.3 = Tavernier Town Shopping Center, Mariners Hospital, Post Office - ZIP 33070, gulfside  

91.0 = Tavernier Creek Bridge; enter Islamorada; Tavernier Creek Marina, Plantation Marina, gulfside 

90.8 = Turek Building, gulfside 

90.1 = Plantation Key Colony community entrance, gulfside; Immanuel Lutheran Church, oceanside. Al large Indian mound existed in the center of the subdivision. 

90.05 = End 4-lane highway if going south

90.0 = Coral Isles Church; Coral Shores High School, Oceanside; Plantation Key Elementary School 

89.5 = San Pedro Catholic Church, gulfside 

88.5 = Plantation Key Government Center, Sheriff, Courthouse, Building/Zoning/Tax Collector/ Assessor; Convalescent and Children's Center; Old Mariner's Hospital, gulfside 

88.0 =  Futura Yacht Club, gulfside; Plaza 88; Plantation Key Professional Building, oceanside 

87.5 = St. James Fisherman Episcopal Church, Executive Bay Club, Gulfside 

87.0 = Founders Park (Plantation Yacht Harbor), gulfside 

86.8 = Treasure Village, Oceanside; Rainbarrel, gulfside 

86.0 = Weigh station for trucks, oceanside WXOS Radio station and tower, Venetian Shores subdivision  

85.5 = Snake Creek Draw Bridge; Coast Guard Station, gulfside Enter Windley Key 

85.3 = Windley Key State Fossil Reef Geological Site, gulfside 

84.3 = This was the center of the community of Quarry that thrived during the construction of the railroad. 

84.2 = Theater of the Sea; Holiday Isle Resort oceanside  

84.0 = Whale Harbor Bridge

83.4 = Island Christian School, gulfside; Whale Harbor Inn, oceanside 

82.2 = Islamorada Chamber of Commerce Red Caboose 

82.6 = Islamorada Post Office- ZIP 33036, oceanside 

81.5 = Islamorada Library and park, gulfside; Hurricane Memorial; Cheeca Lodge, Oceanside. The library was constructed as a Hurricane Refuge School after the 1935 Hurricane.  During construction, the Florida Keys Memorial, know as the Hurricane Monument, was also constructed and dedicated

81.2 = Worldwide Sportsman; gulfside; Moose Lodge 

81.3 = Green Turtle Inn; Oceanside. Part of the structure survived the 1935 Hurricane 

80.0 = Roadside park, gulfside 

79.8 = Tea Table Relief Bridge. Papa Joe's Marina, gulfside; Bud and Mary's, oceanside. The north approach washed out during Hurricane Donna, 1960 

79.1 = Tea Table Channel Bridge 

78.0 = Indian Key Bridge. Lignumvitae Key Botanical Site (State) gulfside in distance. Lignumvitae Key Boat Ramp gulfside; Indian Key Archaeological Site, San Pedro Underwater State Park and Alligator Lighthouse, oceanside at a distance. This is area is of historic significance. The islands of Indian Key, Lignumvitae Key and Alligator Lighthouse are prominent artifacts. 

77.1 = Lignumvitae Bridge  

77.0 = Robbie's Marina, gulfside; Star of the Sea motel, oceanside  

74.0 = Angelo's Country Store, Port Antigua community, gulfside 

74.3 = Safety Harbor community entrance, gulfside 

73.6 = Boy Scouts Sea Base, gulfside; Calusa Cove Marina. Oceanside. gulfside was the location of Camp 3 for WW1 Veterans.  Many perished in the 1935 Hurricane.  

73.4 = Anne's Beach, Oceanside. Gulfside is Veteran's Island, which is the grown over approach to the veteran's bridge piers. 

73.0 = Off shore on the gulfside can be seen the remains (8) of the concrete bridge piling built by the WW-1 veterans. 

72.8 = Apogee of Channel #2 bridge 

71.8 = Craig Key. Rowland Craig built his resort of Craig at the north end of this railroad fill. The drawbridge tender for the Channel 5 railroad bridge lived at the south end. 

71.4 = Apogee of Channel #5 bridge 

70.0 = Fiesta Key KOA and FKAA pumping station 

68.9 = Tower, oceanside 

68.5 = Layton, Long Key Post Office - ZIP 33001 

68.0 = Solid waste transfer station 

67.5 = Long Key State Park, Oceanside 

66.0 = Outdoor Resorts camp ground 

65.8 = Henry Flagler's Long Key Fishing Camp occupied the southwest end of Long Key. American author, Zane Grey, vacationed and wrote while at this location in the early 1900s. 

64.0 = Middle of Long Key Bridge, If southbound, entering the Middle Keys

62.9 = Conch Key, fire station 

62.2 = Walker's Island (Little Conch Key) 

61.2 = Tom's Harbor Cut Bridge 

61.1 = Entrance to Duck Key; Hawk's Cay resort, Oceanside 

60.6 = Tom's Harbor Channel Bridge 

59.9 = Enter/leave City of Marathon 

58.9 = Grassy Key, Dolphin Research Center 

56.2 = Curry Hammock State Park 

54.6 = Coco Plum 

54.5 = Begin/end 4-lane 

53.5 = Entrance to Village of Key Colony Beach, Oceanside 

53.1 = Vaca Cut Bridge, entering the business district of Marathon next 8 miles. 

52.0 = Marathon County Airport, bayside 

50.0 = Museum of Natural History, Crane Hammock, gulfside; Shopping; High School; Sombrero Beach, oceanside 

48.7  = Fisherman's Hospital, Oceanside; Library, Sheriffs substation, Oceanside; Fla Highway Patrol, FKAA bayside; 

48.3 = Post Office ZIP 33050 oceanside. 

48.0 = Coast Guard, gulfside; turnoff to Boot Key

47.5 = Knight's Key 

47.0 = Begin/end of Seven Mile Bridge, Marathon City limits. To Pigeon Key (old 7-Mile Bridge), gulfside. Pigeon Key visitor's center 

44.8 = Pigeon Key, gulf side 

43.9 = Moser Channel, apogee of Seven-Mile Bridge. Sombrero Light House seen at a distance, oceanside 

41.7 = End of original steel truss railroad bridge and begin concrete arch bridge 

40.0 = End/begin Seven Mile Bridge 

39.9 = Veterans Memorial Park, oceanside 

39.5 = Missouri-Little Duck Channel 

38.8 = Sunshine Key Trailer Park 

38.7 = Ohio- Bahia Honda Channel Bridge 

37.0 = Begin/end a short section of 4-lane highway. 

36.8 = Bahia Honda State Park entrance, oceanside 

36.0 = Bahia Honda Bridge (4-lanes) old railroad camelback bridge, ocean 

35.0 = End/begin 4-lane  

34.7 = Steel Tower 

34.5 = Translator TV tower site, gulfside

34.5 = Girl Scout Camp, oceanside. 

34.1 = Camp Sawyer, Boy Scouts, oceanside

34.0 = West Summerland Key 

33.0 = Spanish Harbor Bridge west end. This potion cut away for good cross-section view.  

31.0 = Lower Keys Chamber of Commerce, Old F.E.C. railway marker, oceanside 

30.2 = Big Pine Key traffic stop light; gulf to Key Deer Rd. and Wilder Road. Shopping Ctr, Prison, Preserve, No Name Key turnoff, gulfslde. Continue to No Name Pub, if you can find it. Bogie Channel Bridge (Old Wooden Fishing Bridge) Camp Big Pine Fishing Lodge on oceanside before bridge. 

30.0 = USPO- ZIP 33043 

29.3 = North Pine Channel Bridge 

28.1 = Little Torch Key.  

28.0 = Torch Channel Bridge 

27.9 = Middle Torch Key. Entrance to Big Torch Key, turnoff gulfside

27.7 = Torch-Ramrod Channel Bridge  

27.0 = Aqueduct Authority on Ramrod Key, oceanside 

26.6 = South Pine Channel Bridge, east end of bridge, oceanside  

27.0 = Ramrod Key

26.0 = Niles Channel Bridge, middle. 

25.5 = East end of bridge, oceanside. 

25.0 - 24.0 = Summerland Key community 

24.8 = Summerland Key Post Office - ZIP 33042 

24.0 = Summerland Key Sea Base 

23.5 = Kemp Channel Bridge,  east end of bridge, oceanside

21.5 = Cudjoe Key Transfer station 

21.0 = Cudjoe Key Subdivision on oceanside. U.S. Navy "Fat Albert" site, gulfside 

20.2 = Bow Channel Bridge to Sugarloaf Key. 

20.0 = Mangrove Momma's gulfside, KOA Campground oeeanside 

19.3 = Crane Blvd. to gulfside, Sugarloaf School  

18.6 = Upper Sugarloaf Key 

18.8 = Park Channel Bridge 

18.5 = Park Key Landfill 

17.8 = North Harris Channel Bridge  

17.6 = Harris Gap Channel Bridge 

17.5 = Lower Sugarloaf Key 

17.0 = Blinking light, Sugarloaf Blvd ocean, gulfside; Sugarloaf Airport and Bat Tower. 

Before blinking 1 light, Gulfside to Sugarloaf Lodge, USPO-ZIP 33040; Fire station. 

Sugarloaf Vol. Fire Dep't, Gulfside. 

16.3 = Harris Channel Bridge 

15.8 = Lower Sugarloaf Channel  Bridge 

15.0 = Gate on gulfside to old U.S. Army transmitter site. Now Radio Marti. Bay Point Park. 

14.6 = Saddlebunch #2 Bridge, Bay Point Subdivision entrance, Oceanside 

14.3 = Saddlebunch #3 Bridge, Saddlebunch Shrs./Bluewater Dr., ocean. 

13.1 = Saddlebunch #4 Bridge 

12.8 = Saddlebunch #5 Bridge 

11.4 = Shark Channel Bridge 

11.2 = Shark Key 

11.0 = Big Coppitt Boat Ramp, oceanside 

10.5 = Seaside Park, Fire house; SR 941 AKA Old Boca Chica Road, Ocean, to Geiger Key. 

10.4 = Porpoise Point entrance, gulfside 

10.0 = Big Coppitt Key 

9.7 = Rockland Channel Bridge 

9.2 = East Rockland Key 

8.5 = Tourist welcome center 

8.4 = Begin/end 4-lanes 

8.0 = NAS Boca Chica Overpass, entrance to N S, ocean. Turnoff from both directions US-1.  

7.0 = Back gate to NAS, closed, oceanside 

6.1 = Boca Chica bridge, middle 

5.2 = Key Haven, ocean turnoff 

5.0 = Stock Island, gulf turnout to Jr. College Road: Dump, FKMH, FKCC, Golf Course, jail 

4.1 = Cow Key Channel Bridge and bear right for  

3.9 = Traffic light. End/begin 4-lane.  Bear left for Flagler Street; Airport; Martello Towers, Higgs Beach and Casa Marina. Bear right for N. Roosevelt; Truman Avenue, Fort Taylor 

3.0 = Sears Town shopping plaza 

2.3 = Salt Run Bridge, N. Roosevelt, Key West 

1.7 = Palm Ave; U.S.C.G. Group; NAS Trumbo 

1.0 = About South Street 

0.0 = Jackson Sq. County Seat; Key West Post Office-ZIP 33040.