diff --git a/apps/game/src/lib.rs b/apps/game/src/lib.rs
index ce045976fe..9050df5a43 100644
--- a/apps/game/src/lib.rs
+++ b/apps/game/src/lib.rs
@@ -553,10 +553,13 @@ fn finish_app_setup(
             }
             Mode::TutorialIntro => sandbox::gameplay::Tutorial::start(ctx, app),
             Mode::Challenges => challenges::ChallengesPicker::new_state(ctx, app),
-            Mode::Sandbox => GameplayMode::PlayScenario(
-                app.primary.map.get_name().clone(),
-                Scenario::default_scenario_for_map(app.primary.map.get_name()),
-                Vec::new(),
+            Mode::Sandbox => SandboxMode::simple_new(
+                app,
+                GameplayMode::PlayScenario(
+                    app.primary.map.get_name().clone(),
+                    Scenario::default_scenario_for_map(app.primary.map.get_name()),
+                    Vec::new(),
+                ),
             ),
             Mode::Proposals => pregame::proposals::Proposals::new_state(ctx, None),
             Mode::Ungap => {
diff --git a/apps/game/src/pregame/mod.rs b/apps/game/src/pregame/mod.rs
index 3a1f49907a..3e953ae32a 100644
--- a/apps/game/src/pregame/mod.rs
+++ b/apps/game/src/pregame/mod.rs
@@ -29,7 +29,7 @@ fn enter_state(ctx: &mut EventCtx, app: &mut App, args: Vec<&str>) -> Box<dyn St
             app,
             GameplayMode::PlayScenario(
                 app.primary.map.get_name().clone(),
-                "empty".to_string(), //Scenario::default_scenario_for_map(app.primary.map.get_name()),
+                Scenario::default_scenario_for_map(app.primary.map.get_name()),
                 Vec::new(),
             ),
         ),
diff --git a/map_model/src/make/transit.rs b/map_model/src/make/transit.rs
index c07bcda082..e8eccef6e7 100644
--- a/map_model/src/make/transit.rs
+++ b/map_model/src/make/transit.rs
@@ -240,8 +240,7 @@ fn create_route(
     };
 
     // Check that the paths are valid
-    let requests = result.all_path_requests(map);
-    for req in &requests {
+    for req in result.all_path_requests(map) {
         if req.start == req.end {
             bail!(
                 "Start/end position and a stop position are on top of each other? {}",
@@ -257,15 +256,10 @@ fn create_route(
             );
         }
 
-        if let Err(err) = map.pathfind(req.clone()) {
+        if let Err(err) = map.pathfind(req) {
             bail!("Created the route, but pathfinding failed: {}", err);
         }
     }
-    for pair in requests.windows(2) {
-        if pair[0].end != pair[1].start {
-            panic!("what? {} vs {} on {}", pair[0], pair[1], result.long_name);
-        }
-    }
 
     map.transit_routes.push(result);
     Ok(())
diff --git a/sim/src/mechanics/car.rs b/sim/src/mechanics/car.rs
index 11d546db98..d7cf6c3cb9 100644
--- a/sim/src/mechanics/car.rs
+++ b/sim/src/mechanics/car.rs
@@ -40,7 +40,10 @@ impl Car {
             self.router.head().get_polyline(map).length()
         };
         if end_dist < start_dist {
-            error!("broken {:?}", self);
+            panic!(
+                "{} trying to make a crossing_state from {} to {} at {}. Something's very wrong",
+                self.vehicle.id, start_dist, end_dist, start_time
+            );
         }
 
         let dist_int = DistanceInterval::new_driving(start_dist, end_dist);
diff --git a/sim/src/mechanics/driving.rs b/sim/src/mechanics/driving.rs
index 533c007902..639756d457 100644
--- a/sim/src/mechanics/driving.rs
+++ b/sim/src/mechanics/driving.rs
@@ -341,21 +341,10 @@ impl DrivingSimState {
                 &self.cars,
                 &self.queues,
             );
-            let idx = if let Some(idx) = dists
+            let idx = dists
                 .iter()
                 .position(|entry| entry.member == Queued::Vehicle(id))
-            {
-                idx
-            } else {
-                error!(
-                    "{} isn't in {:?}?! Dists {:?}   Car {:?}",
-                    id,
-                    self.cars[&id].router.head(),
-                    dists,
-                    self.cars[&id]
-                );
-                return;
-            };
+                .unwrap();
 
             // We need to mutate two different cars in some cases. To avoid fighting the borrow
             // checker, temporarily move one of them out of the map.
@@ -1618,21 +1607,12 @@ impl DrivingSimState {
     }
 
     fn get_car_front(&self, now: Time, car: &Car) -> Distance {
-        if let Some(x) = self.queues[&car.router.head()]
+        self.queues[&car.router.head()]
             .get_car_positions(now, &self.cars, &self.queues)
             .into_iter()
             .find(|entry| entry.member == Queued::Vehicle(car.vehicle.id))
-        {
-            x.front
-        } else {
-            panic!(
-                "get_car_front of {:?} at {} on {:?}... car positions are {:?}",
-                car,
-                now,
-                car.router.head(),
-                self.queues[&car.router.head()]
-            );
-        }
+            .unwrap()
+            .front
     }
 
     /// Does the given car want to over-take the vehicle in front of it?
diff --git a/sim/src/mechanics/intersection.rs b/sim/src/mechanics/intersection.rs
index 94afca2fb0..faf68175de 100644
--- a/sim/src/mechanics/intersection.rs
+++ b/sim/src/mechanics/intersection.rs
@@ -1020,13 +1020,6 @@ impl IntersectionSimState {
                     let head = if let Some(c) = q.laggy_head {
                         c
                     } else {
-                        if q.get_active_cars().is_empty() {
-                            panic!(
-                                "what? look for {} near {}",
-                                car,
-                                cars[&current].router.head()
-                            );
-                        }
                         q.get_active_cars()[0]
                     };
                     if current != head {
diff --git a/sim/src/transit.rs b/sim/src/transit.rs
index 7c8d5324ff..c2265394e2 100644
--- a/sim/src/transit.rs
+++ b/sim/src/transit.rs
@@ -102,12 +102,13 @@ impl TransitSimState {
                     });
                     continue;
                 }
+                // TODO Why're we calculating these again? Use bus_route.all_path_requests(), so
+                // that all the nice checks in the map_model layer are preserved here
                 let req = PathRequest::vehicle(
                     stop1.driving_pos,
                     map.get_ts(bus_route.stops[idx + 1]).driving_pos,
                     bus_route.route_type,
                 );
-                let orig = req.clone();
                 match map.pathfind(req) {
                     Ok(path) => {
                         if path.is_empty() {
@@ -115,11 +116,10 @@ impl TransitSimState {
                         }
                         if stop1.driving_pos != path.get_req().start {
                             panic!(
-                                "will warp! {} to {} for {}.    orig req {}",
+                                "{} will warp from {} to {}",
+                                bus_route.long_name,
                                 stop1.driving_pos,
                                 path.get_req().start,
-                                bus_route.long_name,
-                                orig
                             );
                         }
 
@@ -153,13 +153,6 @@ impl TransitSimState {
             } else {
                 None
             };
-
-            /*for pair in stops.windows(2) {
-                if pair[0].next_stop.as_ref().unwrap().end != pair[1].start {
-                                panic!("what? {} vs {} on {}", pair[0], pair[1], result.long_name);
-                                        }
-            }*/
-
             Route {
                 active_vehicles: BTreeSet::new(),
                 stops,
@@ -297,15 +290,6 @@ impl TransitSimState {
                 self.events
                     .push(Event::BusDepartedFromStop(id, bus.route, stop.id));
                 if let Some(path) = stop.next_stop.clone() {
-                    if stop.driving_pos != path.get_req().start {
-                        panic!(
-                            "warp! {} to {} for {}",
-                            stop.driving_pos,
-                            path.get_req().start,
-                            id
-                        );
-                    }
-
                     bus.state = BusState::DrivingToStop(stop_idx + 1);
                     Router::follow_bus_route(id, path)
                 } else if let Some(path) = route.end_at_border.clone() {