Moving around. Drag to look, scroll to zoom, WASD to travel, Q/E to turn, R/F to zoom, Shift to go faster. Tap a train (or press T) to follow it, then Ride this train (or B) to step inside (click to capture the mouse, then WASD to walk, Shift to sprint, C to crouch, Space to hop, Esc to free the mouse and again to step off; V or the first/third person button on the right switches perspective, and scrolling zooms within it); ← → step between stations; tap a station to circle it, drag to roam freely; M zooms out to the whole-line map (pick somewhere new, or M again to go back); H hides everything. On a touch screen it moves like a map app: drag to move, pinch to zoom, twist to turn, two fingers up or down to tilt, double-tap to zoom in; the compass turns north up, and tapped again switches between 2D and 3D. On foot, a thumb anywhere on the left walks.

Walking a station. When your train stops, walk out through an open door onto the platform. Take the stairs or escalator down to the concourse, through the fare gates, and up the other side to catch a train the other way; walk into any open door to board. Signs show where each platform's trains go, and the hint below counts down to the next one. Press P to start on the platform of the nearest station, and P or Esc to leave. On board, a chime and next station announcements play after each departure when sound is on.

Ride together. Choose a baby hippo, tokay gecko, elephant, Thai macaque or water monitor. While you walk a station or ride, other riders appear on platforms and concourses and inside the same train. Open the riders button (O) to pick your character, colour and hat, send emotes (1–5) and copy an invite link for a private room. Press Enter or / to chat.

About the trains. Positions are estimated from live BangkokTransit arrival times, with run times from the distance between stations and longer stops at interchanges. They are not GPS positions. Until the first live reports arrive (about 20 seconds), and whenever the feed is down, trains run to a timetable model based on BTS's published frequencies: first trains 05:15, about every 3 minutes in weekday peaks and 5–6 minutes off-peak. A live report takes over a timetable train within about 90 seconds of it; otherwise a new train fades in where the report puts it. Trains speed up, slow down or wait at a stop to catch up with each report, and never jump.

Train data now. Connecting…

Music. Lo-fi by Tokyo Music Walker (Colorful Flowers, Morning Station, Sunset Drive, After the Rain, Gotta Go, Ordinary Days and Your Little Wings), licensed under CC BY 3.0. "Local Forecast – Elevator", "Airport Lounge", "Bossa Antigua", "Easy Lemon", "Carefree" and "Wallpaper" by Kevin MacLeod (incompetech.com), licensed under Creative Commons: By Attribution 4.0.

Sound. Near a station, the quiet exterior departure sound is adapted from BTS Skytrains {Siemens EMU A1} on YouTube. It plays outside the train as one pulls away.

Flight sim. The plane is DeJunes' 3D Lowpoly Airplane (a Cessna 152, free to use; simplified). Its lift, drag and stall follow the Cessna 172P in JSBSim (LGPL).

About the city. Track alignment, roads, water, parks and trees come from OpenStreetMap (ODbL); trees in parks are scattered to suggest their cover. Building shapes are from Re:Earth and Overture; each is styled after a Bangkok building type chosen from its size and shape (shophouses, condos, walk-ups, hotels, malls, towers, warehouses, and temple halls inside mapped temple grounds) rather than photographed. Twelve landmarks (Siam Paragon, CentralWorld, Terminal 21, Victory Monument, the Erawan Museum and others) are modelled by hand: outlines and heights from OpenStreetMap, roofs and forms interpreted from satellite imagery; see the landmark catalogue. At night, windows light floor by floor in mixed lamp colours, with beacons on the tall towers. The viaduct, stations and trains are illustrative models: stations are drawn cleanly from measurements of reference models of Mo Chit and Siam, train proportions follow BTS's published four-car dimensions, and the interior follows reference photos in a deliberately simple style. Screen doors appear at the stations BTS has fitted them to. Strap swing is driven by the modelled motion and slightly exaggerated.