The "A" Routes.

These are the main cross-island highways; connecting all main points.

Jamaica used Imperial measurements in 1985; this table reflects that. They've since gone metric. Traffic drives on the left. There are very few miles of dual carriageway, and only a few elevated junctions.

This table is based on the 1985 General Drafting  Esso Map of Jamaica. 

Highway  Number	Destinations and Intermediate Points	Mileages
	Sir William Grant Park-Kingston: JN &   WEST via Spanish Town Road to  Northern , Washington Boulevard at New Haven, St Andrew's Parish	6
Branch	JN  Constant Spring Road At Camper Town  WEST to  JN  main branch-Spanish Town Road	4
	Junction of Kingston Branches WEST via Surrey/Middlesex County Line to  Spanish Town: JN	8
	(Spanish Town Bypass)
	Spanish Town, NORTHWEST to JN  branch at Moneague via  Bog Walk and Ewarton	32
	JN  Branch at Moneauge NORTHWEST to JN  at Saint Ann's Bay  via Clairemont	17
	(Follows North Shore of JA, Presently)  JN  at Saint Ann's Bay WEST to Falmouth via Middlesex/Cornwall County line and Duncans	37
	Falmouth WEST to Montego Bay	23
	Montego Bay WEST to Negril via Lucea: End of	52
	JN  at  Spanish Town WEST to May Pen	22
	(  May Pen Bypass)	(7)
	May Pen WEST To Mandeville	25
	(  Mandeville Bypass)	(5)
	Mandeville WEST to Black River via Middlesex/Cornwall County line and Santa Cruz	46
	Black River WEST to Savanna La Mar: End of	31
	JN ;   at Sir William Grant Park-Kingston  NORTH to JN Northern Branch of  Dunrobin Ave at  Camper Town	4
	JN Northern Branch of  Dunrobin Ave at  Camper Town NORTH To   Northern Shore JN via Surrey/Middlesex County Line and Castleton	28
	JN   Northern Shore NORTH and WEST to Ocho Rios: JN  Branch  via Port Maria	36
Branch	Ocho Rios SOUTH to  JN at Moneage	12
	JN  Branch at Ocho Rios WEST to JN  at Saint Ann's Bay	7
	rounds the eastern third of JA. JN ;  at Sir William Grant Park-Kingston EAST to Morant Bay	32
	Morant Bay EAST and NORTH to Hectors River	21
	Hectors River NORTHWEST to Port Antonio	26
	Port Antonio WEST to Buff Bay    follows the North Shore of JA	19
	Buff Bay WEST to  JN via Sussex/Middlesex County Line and  Annatto Bay( JN is 2 miles west of Annatto Bay)	12

The "B" Routes.

These are regional roads that link smaller localities into the "A" system. Not all of these roads are sealed. Those that aren't are indicated by brown cells.

There are also a few un-numbered roads that are sealed, and provide significant connections. These are shown in grey cells with "NONE" in the number cell.

This table is based on the 1985 General Drafting  Esso Map of Jamaica 

Highway Number	Destinations and Intermediate Points, Counties	Mileages
	Kingston JA NORTH to  at Buff Bay via Newcastle	41 miles
	UNSEALED SECTION from Irish Town to Silver Hill
	Surrey County
	From A-1 at Bog Walk NORTH to  Near Whitehall via Troja, Richmond and Highgate	26 miles
	Middlesex County
NONE	From  South of Highgate EAST to  at Chovey	8 miles
	Middlesex County
	From  at May Pen NORTH to Chapelton	12 miles
	From Chapelton NORTHWEST  Junction at Trout Hall	8 miles
	From Trout Hall(  JN) to Cave Valley	9 miles
	From Cave Valley NORTH to  at Runaway Bay Via Alexandria and Brown's Town	26 miles
	Middlesex County
	From  at Trout Hall WEST to Spaldings via Frankfeild	14 miles
	From Spaldings WEST to  at Sedburgh	3 miles
	Middlesex County
	From  At Mandeville NORTH to Christaina	10 miles
	Middlesex County
	From Christiana NORTH  to  at Rio Bueno  via Albert Town and Ulster Spring	30 miles
	Cornwall County
	From  at Hope Village(East of Mandeville)  NORTHWEST to  at Shooter's Hill	2 miles
	From  at Shooter's Hill WEST to  Middlesex/Cornwall County Line; B-10 JN	15 miles
	Middlesex County
	From  Junction WEST To Maggotty(yes, that's a real name!)	13 miles
	From Maggoty WEST to Ys, then NORTH to Cambridge	25 miles
	From Cambridge NORTH to  at Unity Hall(SW of Montego Bay)  Via Montpielier and Anchovy	11 miles
	Cornwall County
	JN  at Middle Quarters NORTH to Bethel Town via  New Market and Leamington	23 miles
	Bethel Town NORTH to JN  at Montpelier	7 miles
	Cornwall County
	From  At Ferris Cross(east of Savanna-La-Mar) NORTHEAST to  Junction at Shettlewood	13 miles
	Cornwall County
	From  At Savanna-La-Mar NORTH to  South of Lucea	21 miles
	Cornwall County
NONE	From  at Savanna-La-Mar WEST to  at Negril  via Little London Connects western ends of  and	~18miles
	Cornwall County
	From  JN at Middlsex/Cornwall County Line NORTH to Troy	6 miles
	Middlesex County
	From Troy NORTH to  at Duncans via Warsop and Clark's Town	26 miles
	Cornwall County
	From  at Green Park WEST To  at Brown's Town  via Bamboo(5 miles sealed)	16 miles
	From  at Browns Town WEST to Stewart Town on  Middlesex/Cornwall County Line	6 miles
	Middlesex County
	From Stewart Town WEST to  at Falmouth  via Clarks Town	17 miles
	Cornwall County
	From   at Freetown SOUTH to Lionel Town	14 miles
	From Lionel Town WEST To Race Course	5 miles
	From Race Course NORTHWEST To Milk River(Rest)	7 miles
	From Milk River(Rest) NORTH to  at Toll Gate	8 miles
	Middlesex County
NONE	From  at May Pen SOUTH to  at Dawkins Pen  (2 miles north of Lionel Town)	11 miles
	Middlesex County
	From  at Linstead NORTH to  at Oracabessa	35 miles
	Middlesex County
NONE	at Port Morant NORTH to Bath,  Then EAST to  at Golden Grove	14 miles
	Surrey County
NONE	at Santa Cruz SOUTHEAST to Litiz  at Cornwall/Middlesex County Line  via Nain then South to Alligator Pond	20 miles
	Cornwall /Middlesex County
NONE	Windward Road  at roundabout in Harbour View (east of Kingston)  WEST to Norman Manley International Airport and Port Royal:  Norman Manley Highway; Port Royal Main Road	9 miles
	Surrey County

Also of note: Alternate secondary connections between Kingston and Spanish Town can be made via Portmore.

See Jamaican Roadsigns from 1985
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