Short of running through and dropping save points on every chamber, the easiest way to get wherever is to just map or changelevel sp_a4_stop_the_box (chapter 8, chamber 6, as an example) in the dev console.

However, this requires knowing what map is what chamber(s), and is not always obvious. Is there a list to match up the bsp's with the chambers?

2 Answers

Chapter 1 - The Courtesy Call

  1. sp_a1_intro1 - Relaxation Vault
  2. sp_a1_intro2 - Original 1
  3. sp_a1_intro3 - Original 2
  4. sp_a1_intro4 - Original 3 and 4
  5. sp_a1_intro5 - Original 5
  6. sp_a1_intro6 - Original 6
  7. sp_a1_intro7 - Original 7
  8. sp_a1_wakeup - GLaDOS
  9. sp_a2_intro - Original 19

Chapter 2 - The Cold Boot

  1. sp_a2_laser_intro - GLaDOS 1
  2. sp_a2_laser_stairs - GLaDOS 2
  3. sp_a2_dual_lasers - GLaDOS 3
  4. sp_a2_laser_over_goo - GLaDOS 4
  5. sp_a2_catapult_intro - GLaDOS 5
  6. sp_a2_trust_fling - GLaDOS 6
  7. sp_a2_pit_flings - GLaDOS 7
  8. sp_a2_fizzler_intro - GLaDOS 8

Chapter 3 - The Return

  1. sp_a2_sphere_peek - GLaDOS 9
  2. sp_a2_ricochet - GLaDOS 10
  3. sp_a2_bridge_intro - GLaDOS 11
  4. sp_a2_bridge_the_gap - GLaDOS 12
  5. sp_a2_turret_intro - GLaDOS 13
  6. sp_a2_laser_relays - GLaDOS 14
  7. sp_a2_turret_blocker - GLaDOS 15
  8. sp_a2_laser_vs_turret - GLaDOS 16
  9. sp_a2_pull_the_rug - GLaDOS 17

Chapter 4 - The Surprise

  1. sp_a2_column_blocker - GLaDOS 18
  2. sp_a2_laser_chaining - GLaDOS 19
  3. sp_a2_triple_laser - GLaDOS 20
  4. sp_a2_bts1 - GLaDOS 21
  5. sp_a2_bts2

Chapter 5 - The Escape

  1. sp_a2_bts3
  2. sp_a2_bts4 - Turret Assembly Line
  3. sp_a2_bts5 - Neurotoxin Generator
  4. sp_a2_bts6 - Tube ride (no gameplay)
  5. sp_a2_core - Core Swap

Chapter 6 - The Fall

  1. sp_a3_00 - Falling
  2. sp_a3_01 - Ruins
  3. sp_a3_03 - Initiative Intro, Alpha Pump
  4. sp_a3_jump_intro - Blue Gel 1
  5. sp_a3_bomb_flings - Blue Gel 2
  6. sp_a3_crazy_box - Blue Gel 3
  7. sp_a3_transition01 - Beta Pump, Potato

Chapter 7 - The Reunion

  1. sp_a3_speed_ramp - Orange Gel 1
  2. sp_a3_speed_flings - Orange Gel 2
  3. sp_a3_portal_intro - Gamma Pump, White Gel 1
  4. sp_a3_end - Master Pump

Chapter 8 - The Itch

  1. sp_a4_intro - Wheatley intro
  2. sp_a4_tb_intro - Wheatley 1
  3. sp_a4_tb_trust_drop - Wheatley 2
  4. sp_a4_tb_wall_button - Wheatley 3
  5. sp_a4_tb_polarity - Wheatley 4
  6. sp_a4_tb_catch - Wheatley 5
  7. sp_a4_stop_the_box - Wheatley 6
  8. sp_a4_laser_catapult - Wheatley 11
  9. sp_a4_laser_platform - Wheatley 12
  10. sp_a4_speed_tb_catch - Wheatley 15
  11. sp_a4_jump_polarity - Wheatley 16

Chapter 9 - The Part Where…

  1. sp_a4_finale1 - Wheatley 17, This is that part.
  2. sp_a4_finale2
  3. sp_a4_finale3
  4. sp_a4_finale4 - That happened.
  5. sp_a5_credits - Credits
4

Here's the complete list of all single player maps in order, which should give you a reasonable granularity:

sp_a1_intro1 sp_a1_intro2 sp_a1_intro3 sp_a1_intro4 sp_a1_intro5 sp_a1_intro6 sp_a1_intro7 sp_a1_wakeup sp_a2_intro sp_a2_laser_intro sp_a2_laser_stairs sp_a2_dual_lasers sp_a2_laser_over_goo sp_a2_catapult_intro sp_a2_trust_fling sp_a2_pit_flings sp_a2_fizzler_intro sp_a2_sphere_peek sp_a2_ricochet sp_a2_bridge_intro sp_a2_bridge_the_gap sp_a2_turret_intro sp_a2_laser_relays sp_a2_turret_blocker sp_a2_laser_vs_turret sp_a2_pull_the_rug sp_a2_column_blocker sp_a2_laser_chaining sp_a2_triple_laser sp_a2_bts1 sp_a2_bts2 sp_a2_bts3 sp_a2_bts4 sp_a2_bts5 sp_a2_bts6 sp_a2_core sp_a3_00 sp_a3_01 sp_a3_03 sp_a3_jump_intro sp_a3_bomb_flings sp_a3_crazy_box sp_a3_transition01 sp_a3_speed_ramp sp_a3_speed_flings sp_a3_portal_intro sp_a3_end sp_a4_intro sp_a4_tb_intro sp_a4_tb_trust_drop sp_a4_tb_wall_button sp_a4_tb_polarity sp_a4_tb_catch sp_a4_stop_the_box sp_a4_laser_catapult sp_a4_laser_platform sp_a4_speed_tb_catch sp_a4_jump_polarity sp_a4_finale1 sp_a4_finale2 sp_a4_finale3 sp_a4_finale4 sp_a5_credits
1