direction_id

In the trips.txt file there is a direction_id field. This document addresses MARTA's implementation of that field.

Google's specifications only allow the use of 0 or 1 in this field, so it would have been impossible for MARTA to establish 4 different values for the eastbound/westbound/northbound/southbound directional indicators that are commonly used with MARTA routes. One might have wished for MARTA to assign 0 consistently to one non-intersecting pair (for example, northbound and eastbound) and 1 to the opposites of that pair (southbound and westbound) -- but MARTA's GTFS feed does not apply such regularity. I have not been able to identify any kind of regular pattern, so I put together this page to decrypt the usage in the MARTA GTFS feed.

The following table associates the direction_id field with the compass directions used by MARTA. I kept the headsign field as an aide to others in identifying mistakes I may have made. Please bring any such mistakes to my attention at joe@joederose.us, and I'll update this file promptly.

Asssuming I have it correct, a text file suitable for import into your database can be downloaded at direction.txt. Note that this file omits the route_id for the following reasons:

The data can just as easily be linked by the route_short_name field.
The route_id changes when MARTA updates its transit feed, so this table would require a full update for each successive update from MARTA if that field were included; as it is now, this table will require only minor updates, and will generally work even if this table and the MARTA feed are not of the same version.

route_short_name	direction_id	Direction	trip_headsign
1	0	Southbound	1 5 POINTS STATION
			1 5 POINTS STATION VIA CHATTAHOOCHEE AVE
			1 5 POINTS STATION VIA MARIETTA BLVD
	1	Northbound	1 MOORES MILL VIA CHATTAHOOCHEE AVE
	1	Northbound	1 MOORES MILL VIA MARIETTA BLVD
2	0	Westbound	2 NORTH AVE STA
	0	Westbound	2 NORTH AVE STATION VIA NORTH AVE
	1	Eastbound	2 DECATUR STATION VIA NORTH AVE
	1	Eastbound	2 PONCE DE LEON - CANDLER PARK STA
3	0	Eastbound	3 MLK JR DRIVE - FIVE PTS STA
			3 MLK/AUBURN AVE/CANDLER PARK VIA N HIGHLAND
			3 MLK/CANDLER PARK VIA BARFIELD/LAKE AVE
	1	Westbound	3 M L KING DR - H.E.HOLMES STA
			3 MLK//H E HOLMES VIA BARFIELD/N HIGHLAND AVE
			3 MLK/AUBURN AVE/H E HOLMES VIA LAKE AVE
4	0	Southbound	4- THOMASVILLE/MORELAND AVE
	0	Southbound	4- THOMASVILLE/MORELAND AVE VIA REBEL FOREST
	1	Northbound	4 INMAN PARK STATION - VIA REBEL FORREST
	1	Northbound	4-INMAN PARK STATION
5	0	Southbound	5 LINDBERGH STA
5	1	Northbound	5 SANDY SPRINGS - DUNWOODY STA
6	0	Southbound	6 INMAN PARK STA - EMORY
6	1	Northbound	6 LINDBERGH STA - EMORY
8	0	Northbound	8 N.DRUID HILLS - BROKHAVN STA
8	1	Southbound	8 N.DRUID HILLS - AVONDALE STA
9	0	Southbound	9 TONEY VALLEY/PEACHCREST RD
9	1	Northbound	9 TONEY VALLEY / KENSINGTON STA
12	0	Southbound	12 HOWELL MILL-MIDTOWN STA
	0	Southbound	12 MIDTOWN STA VIA NORTH SIDE
	1	Northbound	12 CUMBERLAND VIA NORTHSIDE
			12 HOWELL MILL / CUMBERLAND
			12 HOWELL MILL / N SIDE HIGH SCH
			12 HOWELL MILL-MIDTOWN STA
13	0	Eastbound	13 FAIR ST-DOWNTOWN
13	1	Westbound	13 FAIR ST - W. LAKE STA
15	0	Northbound	15 DECATUR STA VIA S. DEKALB MALL
	0	Northbound	15 DECATUR STATION
	1	Southbound	15 S. DEKALB - COUNTY LINE
			15 S. DEKALB - PERIMETER COLL.
			15 S. DEKALB - PERIMETER COLL. VIA S. DEKALB MALL
16	0	Southbound	16 NOBLE- DOWNTOWN
16	1	Northbound	16 NOBLE-EXECUTIVE PARK
19	0	Northbound	19 CLAIRMONT - CHAMBLEE STA
	0	Northbound	19 VA HOSPITAL
	1	Southbound	19 CLAIRMONT - DECATUR STA
			19 CLAIRMONT - DECATUR STA VIA HLTH CTR
			19 DECATUR STATION
21	0	Westbound	21 MEMORIAL DR - GA STATE STATION
	0	Westbound	21 MEMORIAL DR - KING MEM STA
	1	Eastbound	21 MEMORIAL DR - KENSINGTON STA
	1	Eastbound	21 MEMORIAL DR- CRIM HIGH
24	0	Westbound	24 CANDLER PARK STATION
24	1	Eastbound	24 EAST LAKE STATION
25	0	Southbound	25 LENOX STA
	1	Northbound	25 DORAVILLE STA
	1	Northbound	25 MEDICAL CENTER STA
26	0	Eastbound
26	1	Westbound
27	0	Southbound	27 CHESHIRE BRDG / MIDTOWN STA
27	1	Northbound	27 CHESHIRE BRDG / LINDBERGH STA
30	0	Westbound	30 LINDBERGH STA
30	1	Eastbound	30 LAVISTA RD-NORTHLAKE
32	0	Northbound	32 BOULDERCREST - CIVIC CENTER STATION
	0	Northbound	32 BOULDERCREST -FIVE POINTS STATION
	1	Southbound	32 BOULDERCREST - METRO TRANSITIONAL CENTER
33	0	Southbound	33 BRIARCLIFF RD - LENOX STA
33	1	Northbound	33 BRIARCLIFF RD - CHAMBLEE STA
34	0	Northbound	34 INMAN PARK STA
	0	Northbound	34 INMAN PK STA VIA VICKI LN & CORRAL DR
	1	Southbound	34 GRESHAM PARK CLIFTON HEALTH CTNR.
			34 GRESHAM RD CLIFTON SPRGS HEALTH CTR VIA VICKI LN
			34 GRESHAM RD GA PERIMETER COLL
			34 GRESHAM RD VIA VICKI LN GA. PERIMTER
36	0	Westbound	36 MIDTOWN STA
	0	Westbound	36 N DECATUR / VA HIGHLAND- MIDTOWN STA
	1	Eastbound	36 GRADY HIGH SCH
	1	Eastbound	36 N DECATUR / VA HIGHLAND - AVONDALE STA
37	0	Southbound	37 DEFOORS FERRY / ATLANTIC STATION-ARTS CTR STA
37	1	Northbound	37 DEFOORS FERRY / ATLANTIC STATION-MARIETTA BLVD
39	0	Southbound	39 BUFORD HWY - LINDBERGH STA
39	1	Northbound	39 BUFORD HWY - DORAVILLE STA
42	0	Northbound	42 PRYOR RD/MCDANIEL ST-FIVE POINTS STATION
	0	Northbound	42 PRYOR RD/MCDANIEL ST-FIVE POINTS STATION VIA AMAL DR
	1	Southbound	42 PRYOR RD/ MCDANIEL ST-LAKEWOOD STATION
	1	Southbound	42 PRYOR RD/ MCDANIEL ST-LAKEWOOD STATION VIA AMAL DR
47	0	Southbound	47 I-85 ACCESS RD/BRIARWOOD RD - BROOKHAVEN
47	1	Northbound	47 I-85 ACCESS RD/BRIARWOOD RD - CHAMBLEE
49	0	Northbound	49 MCDONOUGH BLVD - FIVE PTS STATION
49	1	Southbound	49 MCDONOUGH BLVD
50	0	Eastbound	50 HOLLOWELL PWY BANKHEAD STA VIA DARNELL CTR
			50 HOLLOWELL PWY VIA CARROLL HGTS
			50 HOLLOWELL PWY VIA CARROLL HGTS/DARNELL CTR
			50 HOLLOWELL PWY-BANKHEAD STA
	1	Westbound	50 HOLLOWELL PWY
	1	Westbound	50 HOLLOWELL PWY VIA CARROLL HGTS
51	0	Eastbound	51 BOONE BLVD / FIVE POINTS STA
	0	Eastbound	51 BOONE BLVD / FIVE POINTS STA VIA COLL HGTS APTS
	1	Westbound	51 BOONE BLVD / W LAKE STA
	1	Westbound	51 BOONE BLVD / W LAKE STA VIA COLL HGTS APTS
53	0	Eastbound	53 SKIPPER DR/W LAKE AVE - W LAKE STA
53	1	Westbound	53 SKIPPER DR/W LAKE AVE
55	0	Southbound	55 JONESBORO RD/HUTCHENS RD
55	1	Northbound	55 JONESBORO RD- FIVE POINTS STATION
56	0	Eastbound	56 H E HOLMES STATION
	0	Eastbound	56 H E HOLMES STATION VIA ALEX DR
	1	Westbound	56 COLLIER HGTS/ADAMSVILLE/PLAINVILLE
			56 COLLIER HGTS/BOULDER PARK
			56 COLLIER HGTS/BOULDER PARK VIA ALEX DR
58	0	Eastbound	58 BANKHEAD STA
58	1	Westbound	58 ATLANTA INDUSTRIAL/HOLLYWOOD RD
60	0	Southbound	60 HAMILTON E. HOLMES STA
60	1	Northbound	60 MOORES MILL SHOPPING CTR
66	0	Northbound	66 LYNHURST / BE MAYS HS
	0	Northbound	66 LYNHURST / HAMILTON E. HOLMES STA
	1	Southbound	66 LYNHURST DR/ BARGE RD P/R
67	0	Westbound	67 WEST END / W LAKE STATION
67	1	Eastbound	67 WEST END-WEST END STA
68	0	Eastbound	68 DONNELLY TO ASHBY ST. STA. VIA WEST END STA.
	1	Westbound	68 DONNELLY TO S GORDON VIA WEST END STATION
	1	Westbound	68 DONNELLY/BEECHER VIA WEST END STATION
71	0	Eastbound	71 WEST END STA
	1	Westbound	71 CASCADE-ASHLEY COURTS
	1	Westbound	71 CASCADE-COUNTRY SQUIRE
73	0	Northbound	73 H E HOLMES STA VIA BAKERS FRY
			73 H E HOLMES STA VIA WENDELL DR
			73 H E HOLMES STATION
	1	Southbound	73 FULTON IND - LAGRANGE/BOAT ROCK
			73 FULTON IND - LAGRANGE/BOAT ROCK VIA WENDELL DR
			73 FULTON IND BAKERS FRY
			73 FULTON IND BAKERS FRY VIA WENDELL DR
74	0	Westbound	74 FLAT SHOALS FIVE POINTS STA
74	1	Eastbound	74 FLAT SHOALS VIA WHITES MILL
75	0	Southbound	75 AVONDALE STA
75	1	Northbound	75 TUCKER
78	0	Westbound	78 CLEVELAND AVE-EAST POINT STATION
78	1	Eastbound	78 CLEVELAND AVENUE
81	0	Northbound	81 WEST END STA
81	1	Southbound	81 VENETIAN / ADAMS PARK
82	0	Westbound	82 CAMP CREEK MARKET PLACE
			82 CAMP CREEK/WELCOME ALL VIA CAMP CREEK MARKET PLACE
			82 CAMP CREEK/WELCOME ALL VIA GA DOR
	1	Eastbound	82 COLLEGE PARK STATION
			82 COLLEGE PARK STATION VIA GA DOR
			82 COLLEGE PARK STATION VIA MARKET PLACE
83	0	Eastbound	83 OAKLAND CITY STA
83	1	Westbound	83 CAMPBELLTON TO GREENBRIAR/BARGE RD P/R
84	0	Eastbound	84 EAST POINT STA
84	1	Westbound	84 EAST POINT / CAMP CREEK MARKET PL
85	0	Southbound	85 N. SPRINGS STA - VIA MANSELL RD
85	1	Northbound	85 ROSWELL / MANSELL P/R
86	0	Westbound	86 EAST LAKE STA
86	1	Eastbound	86 FAIRINGTON RD/MCAFEE RD/STONECREST MALL
87	0	Southbound	87 DUNWOODY STATION
	1	Northbound	87 NORTH SPRINGS STA
	1	Northbound	87 ROSWELL RD N SPRINGS STA
89	0	Northbound	89 COLLEGE PK STA VIA CADIZ
	0	Northbound	89 COLLEGE PK STA VIA HILLINGDALE
	1	Southbound	89 S. FULTON P/R VIA CADIZ
	1	Southbound	89 S. FULTON P/R VIA HILLANDALE
93	0	Eastbound	93 EAST PT STA VIA NORMAN BERRY DR
93	1	Westbound	93 EAST PT STA VIA DELOWE DR
95	0	Northbound	95 WEST END STATION
	1	Southbound	95 ATL AREA TECH METRO COLL
			95 METROPOLITAN PARKWAY-HAPEVILLE
			95 METROPOLITAN PARKWAY-TRADEPORT
99	0	Southbound	99 BOULEVARD/MONROE/GA STATE STA
	0	Southbound	99 BOULEVARD/MONROE/GA STATE STA VIA KING MEM
	1	Northbound	99 BOULEVARD MONROE- NORTH AVE STATION VIA KING MEM
	1	Northbound	99 BOULEVARD/MONROE/MIDTOWN STA
103	0	Southbound	103 CHAMBLEE STA
103	1	Northbound	103 PEELER RD-N. SHALLOWFORD
104	0	Northbound	104 WINTERS CHAPEL RD
104	1	Southbound	104 DORAVILLE STA
107	0	Westbound	107 GLENWOOD RD / INMAN PK STA
107	1	Eastbound	107 GLENWOOD RD / KENSINGTON STA
110	0	Northbound	110 THE PEACH - LENOX STA- BUCKHEAD
	0	Northbound	110 THE PEACH - LENOX STA- BUCKHEAD - VIA ARTS CTR STA
	1	Southbound	110 THE PEACH - FIVE PTS STA - DOWNTOWN
	1	Southbound	110 THE PEACH- ARTS CTR STATION
111	0	Northbound	111 INDIAN CREEK STA
	0	Northbound	111 INDIAN CREEK VIA A WILLIAMS TOWERS
	1	Southbound	111 SNAPFINGER WOODS DR/STONECREST
	1	Southbound	111 SNAPFINGER WOODS DR/STONECREST VIA A WILLIAMS TOWERS
114	0	Northbound	114 AVONDALE STA
114	1	Southbound	114 COLUMBIA DR
115	0	Northbound	115 INDIAN CREEK STATION
115	1	Southbound	115 COVINGTON HWY / S HAIRSTON RD / EVANSMILL P/R
116	0	Westbound	116 INDIAN CREEK VIA HEALTH CENTER
	0	Westbound	116 INDIAN CREEK STA
	1	Eastbound	116 REDAN RD - STONECREST
117	0	Southbound	117 ROCKBRIDGE RD / PANOLA RD / GRTA P/R
	0	Southbound	117 ROCKBRIDGE RD / PANOLA RD / GRTA P/R VIA LOU WALKER CENTER
	1	Northbound	117 ROCKBRIDGE RD/PANOLA RD/KENSINGTON STA
	1	Northbound	117 ROCKBRIDGE RD/PANOLA RD/KENSINGTON STA VIA LOU WALKER CENTER
119	0	Westbound	119 KENSINGTON STA
119	1	Eastbound	119 N HAIRSTON RD MEMORIAL DR P/R
120	0	Westbound	120 AVONDALE STATION
	0	Westbound	120 AVONDALE STATION VIA TUCKER
	1	Eastbound	120 E PONCE / TUCKER ANDREWS HIGH SCH
	1	Eastbound	120 E PONCE DE LEON / TUCKER
121	0	Westbound	121 KENSINGTON STATION
			121 KENSINGTON STATION VIA E PONCE / JULIETTE RD
			121 KENSINGTON STATION VIA STONE MOUNTAIN
	1	Eastbound	121 MEMORIAL DR - DEKALB E CAMPUS
			121 MEMORIAL DR P/R VIA E PONCE / JULIETTE RD
			121 MEMORIAL DR VIA STONE MOUNTAIN
123	0	Southbound	123 BELEVEDERE
	0	Southbound	123 DECATUR STATION
	1	Northbound	123 NORTH DEKALB MALL
124	0	Westbound	124 DORAVILLE STA
124	1	Eastbound	124 PLEASANTDALE-CHMBLE-TUCKR
125	0	Northbound	125 NORTH LAKE MALL
	1	Southbound	125 AVONDALE STATION
	1	Southbound	125 AVONDALE STATION VIA BANK OF AMERICA
126	0	Eastbound	126 N LAKE MALL VIA CHAMBLEE-TUCKER
			126 N LAKE MALL VIA PRES PKWY
			126 N LAKE MALL VIA S FLOWERS
	1	Westbound	126 CHAMBLEE STA VIA S FLOWERS
			126 CHAMBLEE STATION VIA CHAMBLEE-TUCKER
			126 CHAMBLEE STATION VIA PRES PKWY
132	0	Southbound	132 CHAMBLEE STA
132	1	Northbound	132 TILLY MILL / DUNWOODY CLUB
140	0	Southbound	140 N. SPRINGS STA
	1	Northbound	140 NORTH POINTE/MANSELL P/R-HAYNES BRDG RD.
	1	Northbound	140 NORTH POINTE/MANSELL P/R-WINDWARD PKWY
143	0	Southbound	143 N. SPRINGS STA
			143 N. SPRINGS STA VIA MORRIS RD
			143 N. SPRINGS STA VIA WEBB RD
	1	Northbound	143 WINDWARD P/R
			143 WINDWARD P/R VIA MORRIS RD
			143 WINDWARD P/R VIA WEBB RD
148	0	Westbound	148 RIVEREDGE PKWY
148	1	Eastbound	148 MEDICAL CTR STATION
150	0	Westbound	150 DUNWOODY STA
	1	Eastbound	150 PERIMETER CTR/DUNWOODY CLUB
	1	Eastbound	150 PERIMETER CTR/DUNWOODY VILLAGE
153	0	Southbound	153 H E HOLMES STA
153	1	Northbound	153 H E HOLMES-BROWNTOWN
155	0	Northbound	155 GA STATE STA VIA FIVE PTS STA / GRADY HOSP
	1	Southbound	155 POLAR ROCK VIA FIVE PTS/WINDSOR
	1	Southbound	155 SWALLOW CIR VIA FIVE PTS/WINDSOR
162	0	Eastbound	162 OAKLAND CITY STATION
	0	Eastbound	162 OAKLAND CITY STATION VIA N CAMP CK
	1	Westbound	162 HEADLAND DR / ALISON CT
	1	Westbound	162 HEADLAND DR / ALISON CT VIA N CAMP CK
165	0	Eastbound	165 HAMILTON E. HOLMES STA
165	1	Westbound	165 FAIRBURN RD / BARGE RD P/R
170	0	Northbound	170 HAMILTON E HOLMES STATION
	1	Southbound	170 BROWNLEE ROAD / PEYTON
	1	Southbound	170 BROWNLEE ROAD VIA BE MAYS
172	0	Northbound	172 OAKLAND CITY STATION
172	1	Southbound	172 SYLVAN RD - VIRGINIA AVE
178	0	Northbound
	0	Northbound	178 LAKEWOOD STATION
	1	Southbound	178 EMPIRE BLVD / SOUTHSIDE IND PARK
180	0	Northbound	180 COLLEGE PARK STA
180	1	Southbound	180 PALMETTO- VIA FAIRBURN
181	0	Northbound	181 COLLEGE PARK STATION
			181 COLLEGE PARK STATION VIA SOUTH FULTON P&R
			181 COLLEGE PK STATION VIA BANK OF AMERICA
	1	Southbound	181 FAIRBURN VIA: BANK OF AMERICA
			181 FAIRBURN VIA: SOUTH FULTON P&R
			181 SOUTH FULTON PARK RIDE BUFFINGTON ROAD
183	0	Eastbound	183 BARGE RD/LAKEWOOD LAKEWOOD STA
183	1	Westbound	183 BARGE RD/ COUNTY LINE / BARGE RD PARK/RIDE
185	0	Southbound	185 NORTH SPRINGS STA
185	1	Northbound	185 WINDWARD P/R
186	0	Westbound	186 DOWNTOWN
186	1	Eastbound	186 RAINBOW DR/SOUTH DEKALB
189	0	Northbound	189 COLLEGE PARK STATION
189	1	Southbound	189 OLD NATL HWY / UNION STATION
193	0	Southbound	193 EAST POINT STATION - SYLVAN HILLS
193	1	Northbound	193 OAKLAND CITY STATION - SYLVAN HILLS
201	0	Eastbound	201 SIX FLAGS HOLMES STA
	0	Eastbound	201 SIX FLAGS SIX FLAGS PARK
	1	Westbound	201 SIX FLAGS SIX FLAGS PARK
520	0	Westbound	520 MEMORIAL DR BRT LIMITED KENSINGTON STA
520	1	Eastbound	520 MEMORIAL DR BRT LIMITED
521	0	Westbound	521 MEMORIAL DR BRT EXPRESS KENSINGTON STA
521	1	Eastbound	521 MEMORIAL DR BRT EXPRESS
BLUE	0	Eastbound	BLUE EASTBOUND TO INDIAN CREEK STATION
BLUE	1	Westbound	BLUE WESTBOUND TO H E HOLMES STATION
GOLD	0	Northbound	GOLD NORTHBOUND TO DORAVILLE STATION
GOLD	1	Southbound	GOLD SOUTHBOUND TO AIRPORT STATION
GREEN	0	Eastbound	GREEN EASTBOUND TO CANDLER PARK STATION
			GREEN EASTBOUND TO KING MEMORIAL STATION
			GREEN EASTBOUND TO VINE CITY STATION
	1	Westbound	GREEN WESTBOUND TO BANKHEAD STATION
RED	0	Northbound	RED NORTHBOUND TO NORTH SPRINGS STATION
	1	Southbound	RED SOUTHBOUND TO AIRPORT STATION
	1	Southbound	RED SOUTHBOUND TO LINDBERGH STATION

For quick reference, that means:

0 =	1 =	On Routes
Eastbound	Westbound	3, 13, 26, 50, 51, 53, 56, 58, 68, 71, 83, 84, 93, 126, 162, 165, 183, 201, BLUE, GREEN
Westbound	Eastbound	2, 21, 24, 30, 36, 67, 74, 78, 82, 86, 107, 116, 119, 120, 121, 124, 148, 150, 186, 520, 521
Northbound	Southbound	8, 15, 19, 32, 34, 42, 49, 66, 73, 81, 89, 95, 104, 110, 111, 114, 115, 125, 155, 170, 172, 178, 180, 181, 189, GOLD, RED
Southbound	Northbound	1, 4, 5, 6, 9, 12, 16, 25, 27, 33, 37, 39, 47, 55, 60, 75, 85, 87, 99, 103, 117, 123, 132, 140, 143, 153, 185, 193