diff --git a/README.md b/README.md
index d25145e..2f3ee11 100644
--- a/README.md
+++ b/README.md
@@ -200,6 +200,17 @@ docker run --name postgresql -itd \
   sameersbn/postgresql:9.4-11
 ```
 
+Additionally, creation of PostGIS topology extension can be enabled by specifying `DB_POSTGIS_TOPOLOGY=true`:
+
+
+```bash
+docker run --name postgresql -itd \
+  --env 'DB_NAME=dbname' --env 'DB_POSTGIS=true' --env DB_POSTGIS_TOPOLOGY=true \
+  sameersbn/postgresql:9.4-11
+```
+
+Note that topology extension creation can be enabled only when PostGIS extension is enabled.
+
 *By default the PostGIS extension is disabled*
 
 ## Granting user access to a database
diff --git a/runtime/env-defaults b/runtime/env-defaults
index 854e1c5..6b92ba6 100644
--- a/runtime/env-defaults
+++ b/runtime/env-defaults
@@ -20,3 +20,4 @@ DB_TEMPLATE=${DB_TEMPLATE:-template1}
 
 DB_UNACCENT=${DB_UNACCENT:-false}
 DB_POSTGIS=${DB_POSTGIS:-false}
+DB_POSTGIS_TOPOLOGY=${DB_POSTGIS_TOPOLOGY:-false}
diff --git a/runtime/functions b/runtime/functions
index e5314b3..e5b368a 100755
--- a/runtime/functions
+++ b/runtime/functions
@@ -326,7 +326,10 @@ create_database() {
           if [[ ${DB_POSTGIS} == true ]]; then
             echo "‣ Loading PostGIS extension..."
             psql -U ${PG_USER} -d ${database} -c "CREATE EXTENSION IF NOT EXISTS postgis;" >/dev/null 2>&1
-            psql -U ${PG_USER} -d ${database} -c "CREATE EXTENSION IF NOT EXISTS postgis_topology;" >/dev/null 2>&1
+            if [[ ${DB_POSTGIS_TOPOLOGY} == true ]]; then
+                echo "‣ Loading PostGIS Topology extension..."
+                psql -U ${PG_USER} -d ${database} -c "CREATE EXTENSION IF NOT EXISTS postgis_topology;" >/dev/null 2>&1
+            fi
           fi
 
           if [[ -n ${DB_USER} ]]; then