diff --git a/.travis.yml b/.travis.yml
index b5478c3ac..d53eced8c 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -4,10 +4,12 @@ rust:
 - stable
 - beta
 - nightly
+env:
+- PROJ_VERSION=6.1.0
 before_install:
-- wget https://github.com/OSGeo/proj.4/releases/download/6.0.0/proj-6.0.0.tar.gz
-- tar -xzvf proj-6.0.0.tar.gz
-- pushd proj-6.0.0 && ./configure --prefix=/usr && make && sudo make install && popd
+- wget https://github.com/OSGeo/proj.4/releases/download/${PROJ_VERSION}/proj-${PROJ_VERSION}.tar.gz
+- tar -xzvf proj-${PROJ_VERSION}.tar.gz
+- pushd proj-${PROJ_VERSION} && ./configure --prefix=/usr && make && sudo make install && popd
 matrix:
   include:
   - rust: stable
diff --git a/README.md b/README.md
index f46e9f694..7458cca1a 100644
--- a/README.md
+++ b/README.md
@@ -17,8 +17,8 @@ The KV1 format needs a additional dependency called [Proj.4](https://proj4.org/)
 which allows the transformation of localization coordinates.
 [crates.io](https://crates.io/) provides a
 [`proj`](https://crates.io/crates/proj) crate which is a binding to the C
-library (version 6+). This means you need [Proj.4](https://proj4.org/) version
-6+ installed on your system.  See [Proj.4 installation
+library (version 6.1.0). This means you need [Proj.4](https://proj4.org/)
+version 6.1.0 installed on your system.  See [Proj.4 installation
 instructions](https://github.com/OSGeo/proj.4#installation) or take a look at
 our [Dockerfile](https://github.com/CanalTP/transit_model/blob/kv1/Dockerfile).
 ```
diff --git a/fixtures/kv12ntfs/output/stops.txt b/fixtures/kv12ntfs/output/stops.txt
index 8935ca3d3..cc7c73531 100644
--- a/fixtures/kv12ntfs/output/stops.txt
+++ b/fixtures/kv12ntfs/output/stops.txt
@@ -1,23 +1,23 @@
 stop_id,stop_name,visible,fare_zone_id,stop_lon,stop_lat,location_type,parent_station,stop_timezone,geometry_id,equipment_id
-prefix:16000260,"Meppel, Medisch Centrum",1,,6.216615813082661,52.690511593474085,0,prefix:20695,,,
-prefix:19480230,"Dedemsvaart, Adelaarweg",1,,6.457906994446574,52.59530084658398,0,prefix:20361,,,
-prefix:19480250,"Dedemsvaart, Sportlaan",1,,6.45212039892823,52.596485337025,0,prefix:20362,,,
-prefix:19480290,"Dedemsvaart, Busstation",1,,6.449186115318246,52.599055157654796,0,prefix:20363,,,
-prefix:17000040,"Hoogeveen, Station",1,,6.473556158556734,52.73302085011682,0,prefix:20570,,,
-prefix:17003020,"Hoogeveen, Brinkstraat",1,,6.477214351069105,52.73127977444416,0,prefix:20717,,,
-prefix:17001660,"Hoogeveen, Willemskade",1,,6.477303129414771,52.729490440270425,0,prefix:20718,,,
-prefix:47552005,"Epe, Centrum",1,,5.985359672751249,52.35122871673525,0,prefix:31215,,,
-prefix:47552021,"Epe, Lohuizerweg",1,,5.979506595194961,52.34927186173484,0,prefix:32705,,,
-prefix:47552019,"Epe, Sint Jorisweg",1,,5.987248179549488,52.346527509477895,0,prefix:32704,,,
-prefix:19380313,"Slagharen, Centrum",1,,6.55856169388249,52.62560175029438,0,prefix:20718,,,
-prefix:19380320,"Slagharen, Attractiepark",1,,6.563244278472106,52.620648104442296,0,prefix:20718,,,
-prefix:20361,"Dedemsvaart, Adelaarweg",1,,6.457906994446574,52.59530084658398,1,,,,
-prefix:20362,"Dedemsvaart, Sportlaan",1,,6.45212039892823,52.596485337025,1,,,,
-prefix:20363,"Dedemsvaart, Busstation",1,,6.449186115318246,52.599055157654796,1,,,,
-prefix:20570,"Hoogeveen, Station",1,,6.473556158556734,52.73302085011682,1,,,,
-prefix:20695,"Meppel, Medisch Centrum",1,,6.216615813082661,52.690511593474085,1,,,,
-prefix:20717,"Hoogeveen, Brinkstraat",1,,6.477214351069105,52.73127977444416,1,,,,
-prefix:20718,"Hoogeveen, Willemskade",1,,6.533036367256456,52.6585800983357,1,,,,
-prefix:31215,"Epe, Centrum",1,,5.985359672751249,52.35122871673525,1,,,,
-prefix:32704,"Epe, Sint Jorisweg",1,,5.987248179549488,52.346527509477895,1,,,,
-prefix:32705,"Epe, Lohuizerweg",1,,5.979506595194961,52.34927186173484,1,,,,
+prefix:16000260,"Meppel, Medisch Centrum",1,,6.2166158860471405,52.69051160106322,0,prefix:20695,,,
+prefix:19480230,"Dedemsvaart, Adelaarweg",1,,6.457907070063898,52.59530085423737,0,prefix:20361,,,
+prefix:19480250,"Dedemsvaart, Sportlaan",1,,6.452120474490927,52.59648534466884,0,prefix:20362,,,
+prefix:19480290,"Dedemsvaart, Busstation",1,,6.449186190836316,52.59905516530855,0,prefix:20363,,,
+prefix:17000040,"Hoogeveen, Station",1,,6.473556233092426,52.733020858848604,0,prefix:20570,,,
+prefix:17003020,"Hoogeveen, Brinkstraat",1,,6.477214425648108,52.73127978317494,0,prefix:20717,,,
+prefix:17001660,"Hoogeveen, Willemskade",1,,6.477303204010278,52.72949044898821,0,prefix:20718,,,
+prefix:47552005,"Epe, Centrum",1,,5.985359746795904,52.35122872110869,0,prefix:31215,,,
+prefix:47552021,"Epe, Lohuizerweg",1,,5.979506669211143,52.34927186607629,0,prefix:32705,,,
+prefix:47552019,"Epe, Sint Jorisweg",1,,5.987248253645743,52.34652751382206,0,prefix:32704,,,
+prefix:19380313,"Slagharen, Centrum",1,,6.558561770013159,52.6256017584982,0,prefix:20718,,,
+prefix:19380320,"Slagharen, Attractiepark",1,,6.563244354682038,52.62064811262386,0,prefix:20718,,,
+prefix:20361,"Dedemsvaart, Adelaarweg",1,,6.457907070063898,52.59530085423737,1,,,,
+prefix:20362,"Dedemsvaart, Sportlaan",1,,6.452120474490927,52.59648534466884,1,,,,
+prefix:20363,"Dedemsvaart, Busstation",1,,6.449186190836316,52.59905516530855,1,,,,
+prefix:20570,"Hoogeveen, Station",1,,6.473556233092426,52.733020858848604,1,,,,
+prefix:20695,"Meppel, Medisch Centrum",1,,6.2166158860471405,52.69051160106322,1,,,,
+prefix:20717,"Hoogeveen, Brinkstraat",1,,6.477214425648108,52.73127978317494,1,,,,
+prefix:20718,"Hoogeveen, Willemskade",1,,6.533036442901825,52.658580106703425,1,,,,
+prefix:31215,"Epe, Centrum",1,,5.985359746795904,52.35122872110869,1,,,,
+prefix:32704,"Epe, Sint Jorisweg",1,,5.987248253645743,52.34652751382206,1,,,,
+prefix:32705,"Epe, Lohuizerweg",1,,5.979506669211143,52.34927186607629,1,,,,