diff --git a/assets/layers/lock_outline/lock_outline.json b/assets/layers/lock_outline/lock_outline.json
new file mode 100644
index 0000000000..4488f6800f
--- /dev/null
+++ b/assets/layers/lock_outline/lock_outline.json
@@ -0,0 +1,37 @@
+{
+  "id": "lock_outline",
+  "name": {
+    "en": "Lock area"
+  },
+  "description": {
+    "en": "Small layer showing the outline of the lock waterway, but without containing any information"
+  },
+  "source": {
+    "osmTags": "water=lock"
+  },
+  "minzoom": 15,
+  "title": null,
+  "pointRendering": [
+    {
+      "location": [
+        "point"
+      ],
+      "marker": [
+        {
+          "icon": "circle",
+          "color": "white"
+        }
+      ]
+    }
+  ],
+  "lineRendering": [
+    {
+      "width": 1,
+      "color": "blue"
+    }
+  ],
+  "tagRenderings": [],
+  "allowMove": false,
+  "credits": "Pieter Vander Vennet",
+  "credits:uid": 3818858
+}
diff --git a/assets/layers/waterway/waterway.json b/assets/layers/waterway/waterway.json
new file mode 100644
index 0000000000..f23a5c2e89
--- /dev/null
+++ b/assets/layers/waterway/waterway.json
@@ -0,0 +1,79 @@
+{
+  "id": "waterway",
+  "name": {
+    "en": "Navigable waterways"
+  },
+  "description": {
+    "en": "Waterways which are navigable by small boats, yachts, ..."
+  },
+  "source": {
+    "osmTags": {
+      "and": [
+        "motorboat!=no",
+        "boat!=no",
+        {
+          "or": [
+            "waterway=river",
+            "waterway=canal"
+          ]
+        }
+      ]
+    }
+  },
+  "title": {
+    "en": "{name}"
+  },
+  "pointRendering": null,
+  "lineRendering": [
+    {
+      "color": "blue",
+      "width": {
+        "mappings": [
+          {
+            "if": "waterway=canal",
+            "then": "8"
+          },
+          {
+            "if": "waterway=river",
+            "then": "8"
+          },
+          {
+            "if": "waterway=stream",
+            "then": "6"
+          }
+        ]
+      }
+    }
+  ],
+  "tagRenderings": [
+    "images",
+    "wikipedia",
+    {
+      "id": "type",
+      "question": {
+        "en": "What type of waterway is this?"
+      },
+      "mappings": [
+        {
+          "if": "waterway=river",
+          "then": {
+            "en": "This is a river"
+          }
+        },
+        {
+          "if": "waterway=canal",
+          "then": {
+            "en": "This is a canal"
+          }
+        },
+        {
+          "if": "waterway=stream",
+          "then": {
+            "en": "This is a stream "
+          }
+        }
+      ]
+    }
+  ],
+  "allowMove": false
+}
diff --git a/assets/layers/waterway_lock/license_info.json b/assets/layers/waterway_lock/license_info.json
new file mode 100644
index 0000000000..df32c5e317
--- /dev/null
+++ b/assets/layers/waterway_lock/license_info.json
@@ -0,0 +1,12 @@
+[
+  {
+    "path": "waterway_lock.svg",
+    "license": "CC0-1.0",
+    "authors": [
+      "Oosoom"
+    ],
+    "sources": [
+      "https://commons.wikimedia.org/wiki/File:BSicon_uLOCKSl.svg"
+    ]
+  }
+]
\ No newline at end of file
diff --git a/assets/layers/waterway_lock/waterway_lock.json b/assets/layers/waterway_lock/waterway_lock.json
new file mode 100644
index 0000000000..67315bed6c
--- /dev/null
+++ b/assets/layers/waterway_lock/waterway_lock.json
@@ -0,0 +1,220 @@
+{
+  "id": "waterway_lock",
+  "name": {
+    "en": "Locks"
+  },
+  "description": {
+    "en": "Locks on canals, rivers and other navigable waterways "
+  },
+  "source": {
+    "osmTags": "lock=yes"
+  },
+  "minzoom": 10,
+  "title": {
+    "render": {
+      "en": "{lock_name} Lock {lock_ref} (on {name})"
+    }
+  },
+  "pointRendering": [
+    {
+      "location": [
+        "point",
+        "polygon_centroid",
+        "projected_centerpoint"
+      ],
+      "marker": [
+        {
+          "icon": "circle",
+          "color": "white"
+        },
+        {
+          "icon": "./assets/layers/waterway_lock/waterway_lock.svg"
+        }
+      ],
+      "rotation": "calc( {_direction:centerpoint}deg - 90deg )",
+      "pitchAlignment": "map",
+      "label": {
+        "mappings": [
+          {
+            "if": {
+              "and": [
+                "lock_name~*",
+                "vhf~*"
+              ]
+            },
+            "then": {
+              "en": "{lock_name} (VHF {vhf})"
+            }
+          },
+          {
+            "if": "lock_name~*",
+            "then": {
+              "en": "{lock_name}"
+            }
+          }
+        ]
+      },
+      "labelCssClasses": "bg-white rounded px-2"
+    }
+  ],
+  "lineRendering": [
+    {
+      "width": 1,
+      "color": "blue"
+    }
+  ],
+  "tagRenderings": [
+    "images",
+    {
+      "question": {
+        "en": "What is the maximum width (beam) of boats using this lock?"
+      },
+      "id": "max_length",
+      "render": {
+        "en": "This lock permits boats with a maximum width of {maxwidth}"
+      },
+      "freeform": {
+        "key": "maxwidth",
+        "unit": "length"
+      },
+      "questionHint": {
+        "en": "Omit units if designated in meters. Feet and inches maybe indicated with apostrophes and quotation marks."
+      },
+      "condition": "waterway!=derelict_canal"
+    },
+    {
+      "question": {
+        "en": "What is the maximum length of boats that may use this lock?"
+      },
+      "id": "2_qyvwk0kx77jcmh2",
+      "multiAnswer": false,
+      "freeform": {
+        "key": "maxlength"
+      },
+      "render": {
+        "en": "Boats with a maximum length of {maxlength} may use this lock."
+      },
+      "questionHint": {
+        "en": "Omit units if designated in meters. Feet and inches maybe indicated with apostrophes and quotation marks."
+      },
+      "condition": "waterway!=derelict_canal"
+    },
+    {
+      "question": {
+        "en": "How far does this lock raise or lower a boat?"
+      },
+      "id": "3_sm4v6ow91r2i4kd",
+      "questionHint": {
+        "en": "Omit units if designated in meters. Feet and inches maybe indicated with apostrophes and quotation marks."
+      },
+      "multiAnswer": false,
+      "freeform": {
+        "key": "lock:height",
+        "type": "nat"
+      },
+      "render": {
+        "en": "This lock has a drop height of {lock:height}"
+      },
+      "condition": "waterway!=derelict_canal"
+    },
+    {
+      "question": {
+        "en": "Is this lock automated?"
+      },
+      "id": "4_pwnx07go36rzk54",
+      "mappings": [
+        {
+          "if": "automated=yes",
+          "then": {
+            "en": "This lock is automated (operated from control panel or control room)"
+          },
+          "ifnot": "automated="
+        },
+        {
+          "if": "manual=yes",
+          "then": {
+            "en": "This lock is manually operated (with muscle power)"
+          },
+          "ifnot": "manual="
+        }
+      ],
+      "multiAnswer": true,
+      "condition": "waterway!=derelict_canal"
+    },
+    {
+      "question": {
+        "en": "What is the maximum draft of boats using this lock?"
+      },
+      "id": "5_1sz01guflvjeyx7",
+      "questionHint": {
+        "en": "Omit units if designated in meters. Feet and inches maybe indicated with apostrophes and quotation marks."
+      },
+      "multiAnswer": false,
+      "render": {
+        "en": "The maximum draft of boats using this lock is {draft}."
+      },
+      "freeform": {
+        "key": "draft"
+      },
+      "condition": "waterway!=derelict_canal"
+    },
+    {
+      "question": {
+        "en": "What is the name of this lock?"
+      },
+      "id": "lock_name",
+      "questionHint": {
+        "en": "The numerical reference code can be added in a follow-up question "
+      },
+      "multiAnswer": false,
+      "render": {
+        "en": "This lock is named {lock_name}"
+      },
+      "freeform": {
+        "key": "lock_name"
+      }
+    },
+    {
+      "question": {
+        "en": "Does this lock have a reference number/code?"
+      },
+      "id": "ref",
+      "multiAnswer": false,
+      "render": {
+        "en": "This is lock {lock_ref}"
+      },
+      "freeform": {
+        "key": "lock_ref"
+      }
+    },
+    {
+      "question": {
+        "en": "What VHF channel should be used to communicate with this lock?"
+      },
+      "id": "vhf",
+      "render": {
+        "en": "The VHF channelnis {vhf}"
+      },
+      "freeform": {
+        "key": "vhf"
+      }
+    },
+    "opening_hours_24_7",
+    "phone",
+    {
+      "question": {
+        "en": "What is the name of the waterway that this lock is on?"
+      },
+      "id": "waterway_name",
+      "render": {
+        "en": "The waterway is name <b>{name}</b>"
+      },
+      "freeform": {
+        "key": "name"
+      }
+    }
+  ],
+  "allowMove": false,
+  "credits": "Pieter Vander Vennet",
+  "credits:uid": 3818858
+}
\ No newline at end of file
diff --git a/assets/layers/waterway_lock/waterway_lock.svg b/assets/layers/waterway_lock/waterway_lock.svg
new file mode 100644
index 0000000000..59e3454060
--- /dev/null
+++ b/assets/layers/waterway_lock/waterway_lock.svg
@@ -0,0 +1,16 @@
+<svg xmlns="http://www.w3.org/2000/svg" width="500px" height="500px" viewBox="0 0 500 500">
+<title>BSicon lock complex</title>
+<defs>
+ <linearGradient gradientTransform="rotate(90)" id="gate">
+  <stop offset="0%" stop-color="#000" />
+  <stop offset="33.3%" stop-color="#000" />
+  <stop offset="33.3%" stop-color="#FFF" />
+  <stop offset="66.7%" stop-color="#FFF" />
+  <stop offset="66.7%" stop-color="#000" />
+  <stop offset="100%" stop-color="#000" />
+ </linearGradient>
+</defs>
+<polygon stroke="none" fill="#FFF" points="440,400 340,250 440,100 140,100 40,250 140,400"/>
+<rect width="500" height="100" x="0" y="200" style="fill:#039"/>
+<polygon stroke="url(#gate)" stroke-width="40px" fill="none" points="440,400 340,250 440,100 140,100 40,250 140,400"/>
+</svg>
\ No newline at end of file
diff --git a/assets/layers/waterway_lock/waterway_lock.svg.license b/assets/layers/waterway_lock/waterway_lock.svg.license
new file mode 100644
index 0000000000..1d28ce620d
--- /dev/null
+++ b/assets/layers/waterway_lock/waterway_lock.svg.license
@@ -0,0 +1,2 @@
+SPDX-FileCopyrightText: Oosoom
+SPDX-License-Identifier: CC0-1.0
\ No newline at end of file
diff --git a/assets/themes/narrowboat/narrowboat.json b/assets/themes/narrowboat/narrowboat.json
new file mode 100644
index 0000000000..97d477c5c8
--- /dev/null
+++ b/assets/themes/narrowboat/narrowboat.json
@@ -0,0 +1,37 @@
+{
+  "id": "narrowboat",
+  "title": {
+    "en": "Narrowboat Amenities"
+  },
+  "description": {
+    "en": "Features of interest to narrowboats and similar cruisers on inland waterways. "
+  },
+  "icon": "./assets/layers/waterway_lock/waterway_lock.svg",
+  "startZoom": 5,
+  "startLat": 54.44,
+  "startLon": -5.23,
+  "layers": [
+    "waterway_lock",
+    "waterway",
+    "lock_outline",
+    {
+      "builtin": [
+        "drinking_water",
+        "shower",
+        "toilet"
+      ],
+      "override": {
+        "minzoom": 14
+      }
+    }
+  ],
+  "#layers": [
+    "https://studio.mapcomplete.org/89098/layers/waterway_locks/waterway_locks.json",
+    "https://studio.mapcomplete.org/89098/layers/waterway_sanitary_dump_station/waterway_sanitary_dump_station.json",
+    "https://studio.mapcomplete.org/89098/layers/fuel_dock/fuel_dock.json",
+    "https://studio.mapcomplete.org/89098/layers/water_point/water_point.json",
+    "https://studio.mapcomplete.org/89098/layers/winding_holes/winding_holes.json",
+    "https://studio.mapcomplete.org/89098/layers/marinas/marinas.json",
+    "https://studio.mapcomplete.org/89098/layers/chandler/chandler.json"
+  ]
+}