The PCC Level 2: it is unlocked in "Episode 5: Mama", with it you can build a zip-line.
It's the fastest way to travel and the safest; when you are using a zip-line, Sam can't be touched by BTs.

Function:
Level 1: Connection range 300 meters.
Level 2: Connection range boosted (350 meters), Resistence Boosted (50%).
Level 3: Resistence Boosted (150%)

Materials required to upgrade:
Level 2: 240 Chemicals, 480 Special alloys.
Level 3: 1440 Chemicals, 1440 Special alloys, 300 Chiral crystals.

Remember:
You need to upgrade only one zip-line to boost the range to 700m (Lv.1 - Lv.2 - Lv.1 - Lv.2 - etc.)
You can farm Chemicals with the Spiritualist: 600 Chemicals every S rank delivery.

Here is a video: https://youtu.be/RUSM8CJAkH0
00:38 Capital Knot City
01:51 Waystation West of Capital Knot City
02:49 Ludens Fan
03:47 Distribution Center West of Capital Knot City
05:44 Wind Farm
07:39 Musician
10:04 Port Knot City

This is a map with all preppers connected with only one big zip-line network.

It's a difficult goal to achieve but it's actually possible! It requires al lot of patience, time and combinations (a lot of zip-lines are connected with the specific range of 350m).

Here is the video: https://youtu.be/KP4v1FO2BBw
00:14 Lake Knot City
01:15 Engineer
02:12 Elder
04:07 Distribution Center South of Lake Knot City
04:46 Collector
06:08 Film Director
06:51 Junk Dealer
08:24 Chiral Artist's Studio
10:36 South Lake Knot City
11:19 Mama's Lab
12:37 Cosplayer
14:29 Weather Station
15:46 Roboticist
17:02 Heartman's Lab
18:30 Geologist
19:35 Paleontologist
20:41 Evo-devo Biologist
22:14 First Porter
23:05 Timefall Farm
-
24:15 Weather Station
26:12 First Prepper
26:45 Spiritualist
29:03 Incinerator West of Lake Knot City
29:58 Waystation North of Mountain Knot City
31:31 Craftsman
32:32 Middle Knot City Ruins
33:13 Peter Englert
-
33:24 Craftsman
36:36 First Prepper
37:09 Spiritualist
38:12 Mountaineer
40:12 Distribution Center North of Mountian Knot City
41:42 Novelist's Son
43:09 Photographer
44:38 Doctor
45:41 Mountain Knot City
46:03 Heartman's Lab
48:22 Mountaineer

Of course, my routes can look a bit extreme but everything is tested:
https://youtu.be/CRsVQNYBPoM