Two thousand one hundred and seventy miles, rendered in WebGL.
The wagon-train journey rebuilt inside a hand-written 3D engine: streaming terrain, a chase camera, a full day and night cycle, and weather that follows you across the plains, the Rockies and the Blue Mountains. Eighteen landmarks, four river crossings, five forts, and five travelers whose health you manage all the way to Oregon City.
No engine, no libraries, no assets. The renderer is written by hand against WebGL2: the terrain streams in and is rebuilt as the wagon moves, the oxen walk in their teams, dust kicks up behind the wheels, and the sky runs a full day and night cycle while the weather changes with the region and the month. It all ships as one self-contained HTML file.
Every sound is synthesized at runtime with the Web Audio API, which is what keeps it a single file. Wind, rain, snow and river ambience track the weather and the distance to water, hoofbeats lock to the ox gait, and a generative minor-key music bed brightens as the wagon gets closer to Oregon. All eighteen landmarks, river crossings and forts on the trail are modelled at their real mileages.