diff --git a/scripts/verify_map.luau b/scripts/verify_map.luau
new file mode 100644
index 0000000..4c17639
--- /dev/null
+++ b/scripts/verify_map.luau
@@ -0,0 +1,238 @@
+--!strict
+-- verify_map.luau — automated map regression test.
+--
+-- Run from Linux:
+--   python3 -c "import sys;sys.path.insert(0,'/tmp');import rbx;
+--   print(rbx.call('execute_luau',
+--     {'code':open('scripts/verify_map.luau').read(),'datamodel_type':'Edit'},
+--     wait=90,timeout=600))"
+--
+-- Exits with a PASS/FAIL summary. Every check is a real geometric assertion
+-- against the built map -- no check trusts that a build "ran".
+--
+-- IMPORTANT: this must be run against a map built from CURRENT source. Studio
+-- caches ModuleScripts, so a stale Circuit will silently pass the shape checks
+-- while describing the wrong circuit. Check 1 guards exactly that.
+
+local RS = game:GetService("ReplicatedStorage")
+
+local EXPECT_SAMPLES = 823
+local EXPECT_TUNNEL = 200
+local EXPECT_BRIDGE = 474
+local ROAD_HALF = 24 -- ROAD_WIDTH 48 / 2
+local CAR_HALF_W = 5 -- 10-stud car
+local CAR_HEIGHT = 5.5
+
+local results: { string } = {}
+local failures = 0
+
+local function check(name: string, ok: boolean, detail: string)
+	if ok then
+		table.insert(results, ("  PASS  %-34s %s"):format(name, detail))
+	else
+		failures += 1
+		table.insert(results, ("  FAIL  %-34s %s"):format(name, detail))
+	end
+end
+
+-- Fresh-require the circuit so a cached stale module can't mask a bad build.
+local orig = RS.Shared:FindFirstChild("Circuit")
+if not orig then
+	return "FATAL: ReplicatedStorage.Shared.Circuit missing"
+end
+orig.Name = "_CircuitOld"
+local fresh = orig:Clone()
+fresh.Name = "Circuit"
+fresh.Parent = RS.Shared
+local ok, C = pcall(require, fresh)
+local function cleanup()
+	fresh:Destroy()
+	orig.Name = "Circuit"
+end
+if not ok then
+	cleanup()
+	return "FATAL: Circuit require failed: " .. tostring(C)
+end
+
+local s = C.samples
+local n = #s
+
+-- 1. Source freshness ------------------------------------------------------
+local nTunnel, nBridge = 0, 0
+for i = 1, n do
+	if s[i].tunnel then
+		nTunnel += 1
+	end
+	if s[i].bridge then
+		nBridge += 1
+	end
+end
+check(
+	"circuit is current source",
+	n == EXPECT_SAMPLES and nTunnel == EXPECT_TUNNEL and nBridge == EXPECT_BRIDGE,
+	("samples=%d tunnel=%d bridge=%d"):format(n, nTunnel, nBridge)
+)
+
+-- 2. Loop closure + spacing ------------------------------------------------
+local minGap, maxGap = math.huge, 0
+for i = 1, n do
+	local d = (s[(i % n) + 1].pos - s[i].pos).Magnitude
+	minGap = math.min(minGap, d)
+	maxGap = math.max(maxGap, d)
+end
+check("loop closed & evenly spaced", maxGap - minGap < 5, ("gap %.1f..%.1f studs"):format(minGap, maxGap))
+
+-- 3. Grade is drivable -----------------------------------------------------
+local maxGrade, gradeAt = 0, 0
+for i = 1, n do
+	local a, b = s[i].pos, s[(i % n) + 1].pos
+	local flat = (Vector3.new(b.X, 0, b.Z) - Vector3.new(a.X, 0, a.Z)).Magnitude
+	if flat > 0.1 then
+		local g = math.abs(b.Y - a.Y) / flat
+		if g > maxGrade then
+			maxGrade, gradeAt = g, i
+		end
+	end
+end
+check("max grade drivable (<15%)", maxGrade < 0.15, ("%.1f%% at sample %d"):format(maxGrade * 100, gradeAt))
+
+local map = workspace:FindFirstChild("Map")
+if not map then
+	cleanup()
+	return "FATAL: workspace.Map missing -- run MapBuilder first"
+end
+local exp = map:FindFirstChild("Expressway")
+
+-- 4. Continuous driving surface -------------------------------------------
+local rp = RaycastParams.new()
+rp.FilterType = Enum.RaycastFilterType.Include
+rp.FilterDescendantsInstances = { exp }
+local holes, worstOffset = 0, 0
+for i = 1, n do
+	local hit = workspace:Raycast(s[i].pos + Vector3.new(0, 12, 0), Vector3.new(0, -40, 0), rp)
+	if not hit then
+		holes += 1
+	else
+		worstOffset = math.max(worstOffset, math.abs(s[i].pos.Y - hit.Position.Y))
+	end
+end
+check("no holes in road surface", holes == 0, ("%d gaps, worst offset %.2f studs"):format(holes, worstOffset))
+
+-- 5. Tunnel bore count matches flags --------------------------------------
+local walls, ceilings = 0, 0
+for _, d in ipairs(map:GetDescendants()) do
+	if d.Name == "TunnelWall" then
+		walls += 1
+	elseif d.Name == "TunnelCeiling" then
+		ceilings += 1
+	end
+end
+check(
+	"tunnel bore matches flags",
+	walls == nTunnel * 2 and ceilings == nTunnel,
+	("%d walls (want %d), %d ceilings"):format(walls, nTunnel * 2, nTunnel)
+)
+
+-- 6. Nothing intrudes into the car envelope -------------------------------
+-- Probe sits ON the deck: centre lifted by half the car height, so the box
+-- never dips below the road and false-positives on the pillars beneath it.
+local probe = Instance.new("Part")
+probe.Size = Vector3.new(CAR_HALF_W * 2, CAR_HEIGHT, 20)
+probe.Anchored = true
+probe.CanCollide = false
+probe.Transparency = 1
+probe.Parent = workspace
+
+local op = OverlapParams.new()
+op.FilterType = Enum.RaycastFilterType.Exclude
+op.FilterDescendantsInstances = { probe, exp }
+op.MaxParts = 8
+
+local expected = {
+	KillWall = true,
+	Guardrail = true,
+	TunnelCeiling = true,
+	TunnelLight = true,
+	RoadLight = true,
+	BoxGirder = true,
+	PierCap = true,
+	Cable = true,
+	Baseplate = true,
+}
+
+local intrusions = 0
+local firstHit = ""
+for i = 1, n do
+	local a, b = s[i].pos, s[(i % n) + 1].pos
+	local dir = b - a
+	if dir.Magnitude > 0.1 then
+		-- Pillar tops are flush with the deck (0.00 clearance by design), so the
+		-- probe must sit fully ABOVE the road surface or it clips its own
+		-- supports. Lift a further 1.5 studs of margin.
+		local mid = (a + b) / 2 + Vector3.new(0, CAR_HEIGHT / 2 + 2.0, 0)
+		probe.CFrame = CFrame.lookAt(mid, mid + dir.Unit)
+		for _, h in ipairs(workspace:GetPartsInPart(probe, op)) do
+			-- only judge the NEW map; legacy C1/City trees are separate content
+			local root = h
+			while root.Parent and root.Parent ~= workspace do
+				root = root.Parent
+			end
+			if root == map and not expected[h.Name] then
+				intrusions += 1
+				if firstHit == "" then
+					firstHit = h:GetFullName() .. " @sample" .. i
+				end
+				break
+			end
+		end
+	end
+end
+probe:Destroy()
+check("car envelope clear", intrusions == 0, ("%d intrusions %s"):format(intrusions, firstHit))
+
+-- 7. Supports stay under the deck -----------------------------------------
+local badPillars, minGapUnder = 0, math.huge
+for _, d in ipairs(map:GetDescendants()) do
+	if d.Name == "Pillar" and d:IsA("BasePart") then
+		local top = d.Position.Y + d.Size.Y / 2
+		local best = math.huge
+		for i = 1, n do
+			local flat = (Vector3.new(s[i].pos.X, 0, s[i].pos.Z) - Vector3.new(d.Position.X, 0, d.Position.Z)).Magnitude
+			if flat < best then
+				best = flat
+				if flat < ROAD_HALF then
+					local gap = s[i].pos.Y - top
+					minGapUnder = math.min(minGapUnder, gap)
+					if gap < 0 then
+						badPillars += 1
+					end
+				end
+			end
+		end
+	end
+end
+check(
+	"pillars stay below deck",
+	badPillars == 0,
+	("%d protruding, min clearance %.2f studs"):format(badPillars, minGapUnder == math.huge and 0 or minGapUnder)
+)
+
+-- 8. Asset hygiene ---------------------------------------------------------
+local badSounds = 0
+for _, svc in ipairs({ game:GetService("ServerStorage"), RS, workspace }) do
+	for _, d in ipairs(svc:GetDescendants()) do
+		if d:IsA("Sound") then
+			local _, count = d.SoundId:gsub("rbxassetid://", "")
+			if count > 1 then
+				badSounds += 1
+			end
+		end
+	end
+end
+check("no malformed sound ids", badSounds == 0, ("%d double-prefixed"):format(badSounds))
+
+cleanup()
+
+local header = failures == 0 and ("MAP VERIFY: ALL %d CHECKS PASSED"):format(#results)
+	or ("MAP VERIFY: %d/%d CHECKS FAILED"):format(failures, #results)
+return header .. "\n" .. table.concat(results, "\n")