Draw and edit rivers

Draw rivers through land anchors, join tributaries and split branches. River edits save with your map.

Set Meander from 0 to 10 in the masthead. It applies to all rivers on the map. Zero removes added weaving; five is the default. Changes save with the map and support undo.

Start a river

1. Open an editable map containing land tiles.
2. Select Rivers in the editor toolbar, or press R.
3. Click a land tile's centre or a lake shoreline anchor to choose a source.
4. Hover a neighbouring anchor to preview the curve. Click to add a segment.
5. Continue through neighbouring anchors. Select Deselect or press Escape to stop drawing.

The first segment creates the river. Deselecting a pending source changes nothing.

Land tiles provide centre and side anchors. Shared sides use one anchor.

A river stops at the sea or the edge of mapped terrain. It can also stop inland.

A river cannot start at the sea. Connected water fully surrounded by mapped land counts as a lake and can supply a river. Water connected to unmapped terrain remains sea for river routing.

Extend, fork and join

Click a source to extend upstream. Click a downstream endpoint to extend downstream.

Click an interior anchor and select Fork to create another branch of the same river.

To join a tributary, draw into an anchor with an existing downstream route. The receiving route stays intact.

The joined rivers keep their identities and form one connected system. Drawing stops after a join.

Connections that oppose flow, cross between anchors or create loops are rejected. Two terminating endpoints cannot join.

Flow arrows appear in Rivers mode. Other modes and PNG exports hide the arrows and editing anchors.

Select and change width

Click a river line repeatedly to select its system, river, section and segment. The controls show the current level.

The hexagon cluster beside Rivers holds Width, Selection, Lock, Settings, Deselect and Delete. Selecting an interior anchor also shows Split and Fork. Width cycles through Creek, River and Great River for selected segments. Use Selection to cycle the selection level. Lock level keeps it fixed for repeated edits.

A section ends at a source, endpoint, join or fork. Ordinary anchors do not divide sections.

Choose Creek, River or Great River to apply a width to the selected segments. Mixed means several widths are selected.

New rivers use River width. Extensions and forks inherit the adjoining river width.

Anchors occupied by roads are unavailable to rivers. Crossings between anchors remain separate and show a bridge graphic.

Drag anchors and curves

Smooth river in River settings removes custom bends and rebuilds curves from the anchors and current Meander. It normalizes adjoining angles where valid. Anchor positions, widths and flow stay fixed. Invalid resets leave the saved river unchanged. Undo restores the custom shape.

Drag an existing anchor to preview a new position. An ordinary anchor between two segments becomes a curve handle. Moving close to an available anchor snaps it there. Sources, endpoints, joins, and width changes retain their connections.

Drag a segment sideways to adjust its curve. Smoothing runs before reshaping. When a bend enters neighbouring land, hollow markers show the supporting anchors needed to keep the route valid. Flow direction, river identities, and widths stay intact.

Curve adjustments reuse existing control points and align adjoining curves. Extending a customised river also aligns the new connection. The complete river must preserve valid sources, downstream flow and separate road anchors. Flow loops remain invalid.

Release a valid projection to save the complete edit as one undo action. Escape or an invalid drop cancels it. Roads and rivers keep separate anchors. Export is unavailable during a drag.

To smooth an existing river, choose it in River settings and select Smooth river. Meander remains adjustable after curve edits.

Name a river

Open Settings in the Rivers hexagon cluster. Choose a river, enter its name. The name follows the watercourse in bold body text with a theme-aware halo. PNG exports include these labels. Names support undo and redo. Close saves pending changes before closing the panel.

Settings also adjusts font size, colour, position along the river, distance from its line and curvature. Choose above, on, or below the line. Changes save after two seconds of idle time. River labels default to size 10; increase the size when names are difficult to read. In Follow line layout, increase Smoothing to soften tight bends independently of the river. Gentle arc layout provides a separate Curvature control.

Follow line is the default for routes and Toponym Line labels. Smoothing softens tight turns while retaining successive bends. Letter spacing controls the gaps between characters. Gentle arc preserves the simplified curve, with curvature from 0% (straight) to 500%. Short routes extend the label beyond the line instead of compressing the name; settings explain when this happens. Font halo thickness controls the outline around each letter. It defaults to 2. Set it to 0 to remove the outline. Background tag adds an optional solid background behind the whole name and defaults to off. Its padding and colour are separate from the font halo. Both have colour controls and theme reset buttons. Changes save after two seconds of idle time and appear in PNG exports.

Split or remove rivers

Select an interior anchor and choose Split to remove its touching segments and create a visible gap.

Delete anchor removes every touching segment. Delete selection removes the current line selection.

Disconnected downstream pieces receive separate river identities. Empty rivers are removed.

Painting water or removing terrain beneath rivers requires confirmation. The terrain change and river cleanup share one undo action.

Saving, undo and export

Each added segment is a map action. An opposite-side connection passes through the centre and creates two segment actions.

Use Undo and Redo to reverse river edits. Wait for pending edits to save before closing the map.

PNG export includes rivers beneath terrain art and points of interest.

Automatic routing, flow simulation and separate branch names are unavailable.