diff --git a/layers/transportation/layer.sql b/layers/transportation/layer.sql
index 2fd2d5cbf..fd626242b 100644
--- a/layers/transportation/layer.sql
+++ b/layers/transportation/layer.sql
@@ -8,7 +8,8 @@ $$ LANGUAGE SQL IMMUTABLE STRICT;
 CREATE OR REPLACE FUNCTION layer_transportation(bbox geometry, zoom_level int)
 RETURNS TABLE(osm_id bigint, geometry geometry, class text, subclass text,
 ramp int, oneway int, brunnel TEXT, service TEXT, layer INT, level INT,
-indoor INT, bicycle TEXT, foot TEXT, horse TEXT, mtb_scale TEXT, surface TEXT) AS $$
+indoor INT, bicycle TEXT, foot TEXT, horse TEXT, mtb_scale TEXT, surface TEXT,
+trail_length INT) AS $$
     SELECT
         osm_id, geometry,
         CASE
@@ -38,7 +39,8 @@ indoor INT, bicycle TEXT, foot TEXT, horse TEXT, mtb_scale TEXT, surface TEXT) A
         NULLIF(foot, '') AS foot,
         NULLIF(horse, '') AS horse,
         NULLIF(mtb_scale, '') AS mtb_scale,
-        NULLIF(surface, '') AS surface
+        NULLIF(surface, '') AS surface,
+        NULLIF(trail_length, -1) AS trail_length
     FROM (
         -- etldoc: osm_transportation_merge_linestring_gen7 -> layer_transportation:z4
         SELECT
@@ -50,7 +52,7 @@ indoor INT, bicycle TEXT, foot TEXT, horse TEXT, mtb_scale TEXT, surface TEXT) A
             NULL::boolean AS is_ramp, NULL::int AS is_oneway, NULL as man_made,
             NULL::int AS layer, NULL::int AS level, NULL::boolean AS indoor,
             NULL as bicycle, NULL as foot, NULL as horse, NULL as mtb_scale,
-            NULL AS surface, z_order
+            NULL AS surface, NULL::int AS trail_length, z_order
         FROM osm_transportation_merge_linestring_gen7
         WHERE zoom_level = 4
         UNION ALL
@@ -65,7 +67,7 @@ indoor INT, bicycle TEXT, foot TEXT, horse TEXT, mtb_scale TEXT, surface TEXT) A
             NULL::boolean AS is_ramp, NULL::int AS is_oneway, NULL as man_made,
             NULL::int AS layer, NULL::int AS level, NULL::boolean AS indoor,
             NULL as bicycle, NULL as foot, NULL as horse, NULL as mtb_scale,
-            NULL AS surface, z_order
+            NULL AS surface, NULL::int AS trail_length, z_order
         FROM osm_transportation_merge_linestring_gen6
         WHERE zoom_level = 5
         UNION ALL
@@ -80,7 +82,7 @@ indoor INT, bicycle TEXT, foot TEXT, horse TEXT, mtb_scale TEXT, surface TEXT) A
             NULL::boolean AS is_ramp, NULL::int AS is_oneway, NULL as man_made,
             NULL::int AS layer, NULL::int AS level, NULL::boolean AS indoor,
             NULL as bicycle, NULL as foot, NULL as horse, NULL as mtb_scale,
-            NULL AS surface, z_order
+            NULL AS surface, NULL::int AS trail_length, z_order
         FROM osm_transportation_merge_linestring_gen5
         WHERE zoom_level = 6
         UNION ALL
@@ -95,7 +97,7 @@ indoor INT, bicycle TEXT, foot TEXT, horse TEXT, mtb_scale TEXT, surface TEXT) A
             NULL::boolean AS is_ramp, NULL::int AS is_oneway, NULL as man_made,
             NULL::int AS layer, NULL::int AS level, NULL::boolean AS indoor,
             NULL as bicycle, NULL as foot, NULL as horse, NULL as mtb_scale,
-            NULL AS surface, z_order
+            NULL AS surface, NULL::int AS trail_length, z_order
         FROM osm_transportation_merge_linestring_gen4
         WHERE zoom_level = 7
         UNION ALL
@@ -110,7 +112,7 @@ indoor INT, bicycle TEXT, foot TEXT, horse TEXT, mtb_scale TEXT, surface TEXT) A
             NULL::boolean AS is_ramp, NULL::int AS is_oneway, NULL as man_made,
             NULL::int AS layer, NULL::int AS level, NULL::boolean AS indoor,
             NULL as bicycle, NULL as foot, NULL as horse, NULL as mtb_scale,
-            NULL AS surface, z_order
+            NULL AS surface, NULL::int AS trail_length, z_order
         FROM osm_transportation_merge_linestring_gen3
         WHERE zoom_level = 8
         UNION ALL
@@ -126,7 +128,7 @@ indoor INT, bicycle TEXT, foot TEXT, horse TEXT, mtb_scale TEXT, surface TEXT) A
             NULL::boolean AS is_ramp, NULL::int AS is_oneway, NULL as man_made,
             layer, NULL::int AS level, NULL::boolean AS indoor,
             bicycle, foot, horse, mtb_scale,
-            NULL AS surface, z_order
+            NULL AS surface, NULL::int AS trail_length, z_order
         FROM osm_highway_linestring_gen2
         WHERE zoom_level BETWEEN 9 AND 10
           AND st_length(geometry)>zres(11)
@@ -142,7 +144,7 @@ indoor INT, bicycle TEXT, foot TEXT, horse TEXT, mtb_scale TEXT, surface TEXT) A
             NULL::boolean AS is_ramp, NULL::int AS is_oneway, NULL as man_made,
             layer, NULL::int AS level, NULL::boolean AS indoor,
             bicycle, foot, horse, mtb_scale,
-            NULL AS surface, z_order
+            NULL AS surface, NULL::int AS trail_length, z_order
         FROM osm_highway_linestring_gen1
         WHERE zoom_level = 11
           AND st_length(geometry)>zres(12)
@@ -165,6 +167,13 @@ indoor INT, bicycle TEXT, foot TEXT, horse TEXT, mtb_scale TEXT, surface TEXT) A
             END AS indoor,
             bicycle, foot, horse, mtb_scale,
             surface_value(surface) AS "surface",
+            -- NOTE: You can't just do geometry::geography because the current srid is 900913
+            -- (pseudo mercator). It needs to be in lat/lon, so I first convert to WGS84, then cast
+            -- to geography.
+            CASE WHEN highway IN ('pedestrian', 'path', 'footway', 'cycleway', 'steps', 'bridleway', 'corridor')
+                THEN round(ST_Length(ST_Transform(geometry, 4326)::geography))::int
+                ELSE NULL::int
+            END AS "trail_length",
             z_order
         FROM osm_highway_linestring
         WHERE NOT is_area AND (
@@ -199,7 +208,7 @@ indoor INT, bicycle TEXT, foot TEXT, horse TEXT, mtb_scale TEXT, surface TEXT) A
             NULL::boolean AS is_ramp, NULL::int AS is_oneway, NULL as man_made,
             NULL::int AS layer, NULL::int AS level, NULL::boolean AS indoor,
             NULL as bicycle, NULL as foot, NULL as horse, NULL as mtb_scale,
-            NULL as surface, z_order
+            NULL as surface, NULL::int AS trail_length, z_order
         FROM osm_railway_linestring_gen5
         WHERE zoom_level = 8
             AND railway='rail' AND service = '' and usage='main'
@@ -215,7 +224,7 @@ indoor INT, bicycle TEXT, foot TEXT, horse TEXT, mtb_scale TEXT, surface TEXT) A
             NULL::boolean AS is_ramp, NULL::int AS is_oneway, NULL as man_made,
             layer, NULL::int AS level, NULL::boolean AS indoor,
             NULL as bicycle, NULL as foot, NULL as horse, NULL as mtb_scale,
-            NULL AS surface, z_order
+            NULL AS surface, NULL::int AS trail_length, z_order
         FROM osm_railway_linestring_gen4
         WHERE zoom_level = 9
             AND railway='rail' AND service = '' and usage='main'
@@ -229,7 +238,7 @@ indoor INT, bicycle TEXT, foot TEXT, horse TEXT, mtb_scale TEXT, surface TEXT) A
             is_bridge, is_tunnel, is_ford, is_ramp, is_oneway, NULL as man_made,
             layer, NULL::int AS level, NULL::boolean AS indoor,
             NULL as bicycle, NULL as foot, NULL as horse, NULL as mtb_scale,
-            NULL AS surface, z_order
+            NULL AS surface, NULL::int AS trail_length, z_order
         FROM osm_railway_linestring_gen3
         WHERE zoom_level = 10
             AND railway IN ('rail', 'narrow_gauge') AND service = ''
@@ -243,7 +252,7 @@ indoor INT, bicycle TEXT, foot TEXT, horse TEXT, mtb_scale TEXT, surface TEXT) A
             is_bridge, is_tunnel, is_ford, is_ramp, is_oneway, NULL as man_made,
             layer, NULL::int AS level, NULL::boolean AS indoor,
             NULL as bicycle, NULL as foot, NULL as horse, NULL as mtb_scale,
-            NULL as surface, z_order
+            NULL as surface, NULL::int AS trail_length, z_order
         FROM osm_railway_linestring_gen2
         WHERE zoom_level = 11
             AND railway IN ('rail', 'narrow_gauge', 'light_rail') AND service = ''
@@ -257,7 +266,7 @@ indoor INT, bicycle TEXT, foot TEXT, horse TEXT, mtb_scale TEXT, surface TEXT) A
             is_bridge, is_tunnel, is_ford, is_ramp, is_oneway, NULL as man_made,
             layer, NULL::int AS level, NULL::boolean AS indoor,
             NULL as bicycle, NULL as foot, NULL as horse, NULL as mtb_scale,
-            NULL as surface, z_order
+            NULL as surface, NULL::int AS trail_length, z_order
         FROM osm_railway_linestring_gen1
         WHERE zoom_level = 12
             AND railway IN ('rail', 'narrow_gauge', 'light_rail') AND service = ''
@@ -272,7 +281,7 @@ indoor INT, bicycle TEXT, foot TEXT, horse TEXT, mtb_scale TEXT, surface TEXT) A
             is_bridge, is_tunnel, is_ford, is_ramp, is_oneway, NULL as man_made,
             layer, NULL::int AS level, NULL::boolean AS indoor,
             NULL as bicycle, NULL as foot, NULL as horse, NULL as mtb_scale,
-            NULL as surface, z_order
+            NULL as surface, NULL::int AS trail_length, z_order
         FROM osm_railway_linestring
         WHERE zoom_level = 13
                 AND railway IN ('rail', 'narrow_gauge', 'light_rail') AND service = ''
@@ -287,7 +296,7 @@ indoor INT, bicycle TEXT, foot TEXT, horse TEXT, mtb_scale TEXT, surface TEXT) A
             is_bridge, is_tunnel, is_ford, is_ramp, is_oneway, NULL as man_made,
             layer, NULL::int AS level, NULL::boolean AS indoor,
             NULL as bicycle, NULL as foot, NULL as horse, NULL as mtb_scale,
-            NULL AS surface, z_order
+            NULL AS surface, NULL::int AS trail_length, z_order
         FROM osm_aerialway_linestring_gen1
         WHERE zoom_level = 12
         UNION ALL
@@ -301,7 +310,7 @@ indoor INT, bicycle TEXT, foot TEXT, horse TEXT, mtb_scale TEXT, surface TEXT) A
             is_bridge, is_tunnel, is_ford, is_ramp, is_oneway, NULL as man_made,
             layer, NULL::int AS level, NULL::boolean AS indoor,
             NULL as bicycle, NULL as foot, NULL as horse, NULL as mtb_scale,
-            NULL AS surface, z_order
+            NULL AS surface, NULL::int AS trail_length, z_order
         FROM osm_aerialway_linestring
         WHERE zoom_level >= 13
         UNION ALL
@@ -314,7 +323,7 @@ indoor INT, bicycle TEXT, foot TEXT, horse TEXT, mtb_scale TEXT, surface TEXT) A
             is_bridge, is_tunnel, is_ford, is_ramp, is_oneway, NULL as man_made,
             layer, NULL::int AS level, NULL::boolean AS indoor,
             NULL as bicycle, NULL as foot, NULL as horse, NULL as mtb_scale,
-            NULL AS surface, z_order
+            NULL AS surface, NULL::int AS trail_length, z_order
         FROM osm_shipway_linestring_gen2
         WHERE zoom_level = 11
         UNION ALL
@@ -327,7 +336,7 @@ indoor INT, bicycle TEXT, foot TEXT, horse TEXT, mtb_scale TEXT, surface TEXT) A
             is_bridge, is_tunnel, is_ford, is_ramp, is_oneway, NULL as man_made,
             layer, NULL::int AS level, NULL::boolean AS indoor,
             NULL as bicycle, NULL as foot, NULL as horse, NULL as mtb_scale,
-            NULL AS surface, z_order
+            NULL AS surface, NULL::int AS trail_length, z_order
         FROM osm_shipway_linestring_gen1
         WHERE zoom_level = 12
         UNION ALL
@@ -341,7 +350,7 @@ indoor INT, bicycle TEXT, foot TEXT, horse TEXT, mtb_scale TEXT, surface TEXT) A
             is_bridge, is_tunnel, is_ford, is_ramp, is_oneway, NULL as man_made,
             layer, NULL::int AS level, NULL::boolean AS indoor,
             NULL as bicycle, NULL as foot, NULL as horse, NULL as mtb_scale,
-            NULL AS surface, z_order
+            NULL AS surface, NULL::int AS trail_length, z_order
         FROM osm_shipway_linestring
         WHERE zoom_level >= 13
         UNION ALL
@@ -362,7 +371,7 @@ indoor INT, bicycle TEXT, foot TEXT, horse TEXT, mtb_scale TEXT, surface TEXT) A
             FALSE AS is_ramp, FALSE::int AS is_oneway, man_made,
             layer, NULL::int AS level, NULL::boolean AS indoor,
             NULL as bicycle, NULL as foot, NULL as horse, NULL as mtb_scale,
-            NULL AS surface, z_order
+            NULL AS surface, NULL::int AS trail_length, z_order
         FROM osm_highway_polygon
         -- We do not want underground pedestrian areas for now
         WHERE zoom_level >= 13
diff --git a/layers/transportation/transportation.yaml b/layers/transportation/transportation.yaml
index b92f6504b..b94fbb2ca 100644
--- a/layers/transportation/transportation.yaml
+++ b/layers/transportation/transportation.yaml
@@ -135,10 +135,13 @@ layer:
       values:
       - paved
       - unpaved
+    trail_length:
+      description: |
+          Distance in meters of trail linestring. Only defined for class=path.
   datasource:
     geometry_field: geometry
     srid: 900913
-    query: (SELECT geometry, class, subclass, oneway, ramp, brunnel, service, layer, level, indoor, bicycle, foot, horse, mtb_scale, surface FROM layer_transportation(!bbox!, z(!scale_denominator!))) AS t
+    query: (SELECT geometry, class, subclass, oneway, ramp, brunnel, service, layer, level, indoor, bicycle, foot, horse, mtb_scale, surface, trail_length FROM layer_transportation(!bbox!, z(!scale_denominator!))) AS t
 schema:
   - ./class.sql
   - ./update_transportation_merge.sql