The size of its floor was not found: 100 jō is plausible.
The picture above was drawn when the docs were built. The script below draws it again with the published package.
import { drawKyogijo } from "@johnmorrisdotca/kyogijo-stadiums";
import { placeById, surfaceOf } from "@johnmorrisdotca/kyogijo-stadiums/atlas";
const svg = drawKyogijo({ ...surfaceOf(placeById("kyu-butokuden")), crowd: true });
This page imports the package from jsDelivr (major version 0), which serves only versions that have been published to npm. A feature added after the last release is not in it: the page then keeps the picture above and says why. The docs were built from version 0.6.1.