BERTH

BERTH: An ATB Docking Sim

Dock a 236-metre articulated tug-barge using propulsion, steering, bow thruster and lines.

PC only. The game needs a desktop browser with a keyboard and mouse or a gamepad.
Play now →

Free · Browser · Single-player · PC · Keyboard, mouse or gamepad

Twin screw / Easy / secured alongsideBerth camera / docking console
Top-down view of the tug-barge alongside the quay with its lines made fast, a moored ship astern, and the docking console below.
Secured alongside. Twin screw, Easy: SECURED CLEAN in 3 min 52 s.

01 / Game

An articulated tug-barge, a 216-metre barge with a 40-metre tug in its notch, seen from above. Bring it alongside a quay without damage. Three tugs, four tiers, seven berths.

Lines

LINES

Take a line, then heave, slack, hold or let go. On easier tiers the deck crew does more of the line work.

Contact

CONTACT

Fenders can be landed on. Hard structure cannot. Landing speed and impact are recorded.

Weather

WEATHER

Calm water, then a steady wind, then gusts, then an empty barge.

02 / Screens

Screenshots of the current build (0caff79, 2026-10-03).

Twin screw / Easy / spring swing-inBerth camera
Top-down view of the tug-barge angled toward the quay on its forward line, stern 45 metres off.
Swinging in on the forward line. Slow ahead, rudders 35° to starboard, stern 45 m off. The forward line is at its brake limit.
Easy / twin screwBerth camera
Overhead view of the loaded tug-barge 30 metres off a quay with a moored ship ahead, calm water, docking console below.
Easy, calm water. Bow 30 m off the fenders, a moored ship ahead.
Twin screw / EasySTERN camera focus
Close view of the tug in the barge notch, both rudders over, the unit angled toward the quay on the forward line.
Stern camera. Both rudders 35° to starboard, 10 % pitch.
Twin screw / EasyAlongside
The barge flat along the quay, bow and stern readouts near zero knots.
Alongside. Bow 0 kn and 0.3 m off, stern 0 kn and 8.4 m off.
Hard / VecTwinBerth camera
The unit off the quay in gusting wind, the VecTwin console with its round joystick between the two rudder dials.
Hard, VecTwin. Joystick on STERN TO STBD. Wind 20 to 35 kn, gusting, off the berth.
Mastery / twin screwNight lights
Night view of the empty barge with deck and quay lights, 62 metres off the quay, bow thruster marked not fitted.
Mastery at night. Empty barge, no bow thruster. Wind 20 to 35 kn, gusting, off the berth.

03 / Features

  • The unit236 m articulated tug-barge, loaded or empty, moving as one rigid unit.
  • Three tugsSingle screw, twin screw, and a single prop with two wide-angle rudders on a joystick. Each has its own drills and progress.
  • Bow thrusterControllable pitch, with start-up time and thrust that fades with speed.
  • Winches and crewWinch brake, constant tension and per-line orders. Crew help varies by tier.
  • ContactFender, hard-structure and moored-vessel contact, with landing speed in m/s.
  • TiersFour per tug: calm, steady wind, gusts, and an empty barge with no thruster.
  • BerthsThe tight berth with the tier ladder, plus six preview berths.
  • MomentumCompressed by default, so a berth takes five to eight minutes. Full momentum is one setting.
  • DrillsFive per tug: open water, spin, walk sideways, stop from 3 kn, spring-line swing-in.
  • Docking displayBow and stern closing speeds, heading, rate of turn, metres off at each end.
  • ViewsSeveral cameras with zoom, night lights, and an underwater view of the props and rudders.
  • SoundEngine, thruster, lines, contact, wind and water.
  • ReplaysEvery attempt can be replayed from its recorded inputs, exported and imported.
  • LeaderboardPer berth, tug, tier and momentum. Runs are listed after a re-run check, and can be watched and commented on.
  • ControlsKeyboard, mouse on the console, or gamepad. Controls card on F1.
  • ProgressClean results unlock tiers per tug. Personal bests are saved in your browser.
  • GuidanceA guidance line with the next step. Less help on harder tiers, none on Hard.

04 / Tugs

Three tugs. Three control setups.

Station 01Learner

SIMPLE

One pitch lever, one rudder, follow-up steering.

Station 02Link available

TWIN SCREW

Two pitch levers, two rudders: linked, split or independent. Follow-up or non-follow-up steering.

Station 03Joystick

VECTWIN

One pitch lever and a joystick for two wide-angle rudders behind one prop.

05 / Tiers

Four tiers.

Two clean results on a tier unlock the next one for that tug.

Tier 01Open

EASY

No wind. The deck crew handles the lines.

WindNone
BargeLoaded
ThrusterFitted
CrewAutomatic
Tier 02Unlock

MEDIUM

Steady wind. You call the lines.

WindSteady 12 kn, off the berth
BargeLoaded
ThrusterFitted
CrewOn your orders
Tier 03Unlock

HARD

Gusts. Manual winches. No hints.

Wind20 to 35 kn, gusting, off the berth
BargeLoaded
ThrusterFitted
CrewManual
Tier 04Unlock

MASTERY

Gusts, an empty barge, no bow thruster.

Wind20 to 35 kn, gusting, off the berth
BargeEmpty
ThrusterNot fitted
CrewManual

06 / How to play and requirements

Controls, lines, tiers and common mistakes: How to play.

MinimumRecommended
BrowserChrome or Edge, current versionChrome, current version
OSWindows, macOS or Linux with Chrome or EdgeWindows 11
Display1280 x 7201920 x 1080
GraphicsIntegrated graphicsAny
InputKeyboard, or mouseKeyboard and mouse, or a gamepad
StorageUnder 20 MB. Progress is saved in your browser.
NetworkTo load the page, and for the leaderboard.

No phone or tablet version. Firefox and Safari are untested; leaderboard runs recorded in them may fail the check. Clearing site data clears your progress.

Not modelled
  • Current, ice, shallow-water effect, bank suction and waves. Wind is the only environment.
  • Prop walk.
  • Articulation between tug and barge. The unit is rigid.
  • Real vessels, ports, companies or bridge layouts. Everything is fictional.

Play

Start on Easy.

No wind. The deck crew handles the lines.

Play now →