diff --git a/config/terrain_movement.yaml b/config/terrain_movement.yaml
index c3f8a76..b4e0db2 100644
--- a/config/terrain_movement.yaml
+++ b/config/terrain_movement.yaml
@@ -10,7 +10,14 @@ polar_snow_line_base_km: 2.5        # Base snowline at temperate latitudes
 polar_snow_factor_start: 0.40       # Latitude distFromCenter where polar cooling starts
 polar_snow_factor_end: 0.85         # Latitude distFromCenter where sea-level snowline is reached
 
-# Movement costs per terrain type (1.0 = normal base cost, higher values = slower traversal)
+# Slope and elevation movement penalties
+# Elevation difference (deltaH in km) between hex centers
+uphill_slope_multiplier: 4.0         # Penalty added per km of elevation gained (uphill)
+downhill_slope_bonus_multiplier: 2.0 # Bonus deducted per km of elevation lost (downhill)
+min_step_cost: 0.25                  # Minimum possible step cost after downhill bonus
+max_climbable_slope_km: 1.2          # Maximum elevation rise per hex step; higher slopes are impassable cliffs
+
+# Movement base costs per terrain type (1.0 = normal base cost, higher values = slower traversal)
 movement_costs:
   grasland: 1.0
   bos: 2.0