Introduction:
Fast travel is a system that serves two goals. First, it allows adventurers to venture further into the wilderness by starting from a point of relative safety within the wilderness. Second, it allows certain types of sessions, like dungeon crawls, to have the time needed to complete them. Below are the general rules and guidelines for fast travel.
Unlocking Fast Travel to a Location:
Characters can always begin an adventure (Session) from a stronghold they control in the wilderness. For example, if a character has access to a ship, their adventuring group can begin their adventure aboard the ship rather than starting at a settlement. This will become critical in later adventures as characters travel further and further from the settlements.
Characters can also begin a session from a safe location in a wilderness region. These are typically referred to as hubs. Some examples of hubs are the Riverfolk Village (Narrow Pines), Covenna (Bastion Mountains), Ozerick's Tower (Crowned Forest), and Calaena's Cove (Crowned Forest). As long as the hub remains safe and friendly to the adventurers it can be fast traveled to and the adventure can start a little bit close to your destination. However, events can transpire that make a hub unavailable for fast travel. For example, Covenna was not available for fast travel while occupied by goblin forces.
When player characters (not players) have been to a location previously they have the ability to fast travel to that location. Fast travel requires that at least one character in an adventuring group has discovered the location that the group wishes to fast travel to. For example, characters A, B, C, and D wish to fast travel to location 1 that character A has been to. This group is able to do so because at least one character (A) has been to the location.
Alternatively, there may be NPCs that allow a group to fast travel to a location. For example, capturing an NPC may allow characters to gain information concerning the faction that NPC is tied to, including the location of a stronghold. This requires the capture of an NPC, returning that NPC to a safe location like a settlement or Stronghold, and then the use of downtime to interrogate that NPC. But interrogated one NPC is unlikely to reveal everything about a location. Fast traveling on interrogation information alone can be risky.
Fast Travel:
If a party elects to fast travel they forego the typical benefits of exploration. Notably, they will not find points of interest along the way or have random encounters that may reveal information. Additionally, the adventurers are locked-in to completing an objective/quest/goal associated with the location they travel to. For example, if characters fast travel to the Lost Temple Ruins they must explore the Lost Temple Ruins they cannot use it as a means to get closer to another point of interest. Fast Travel is meant to allow the players to interact with specific points of interest without the need to play through the travel portion of a session.
Getting to the Location and the Adventure:
Upon arrival, the characters will be advised as to the condition they arrived in. They may arrive missing some resources or health or in prime condition ready to fight. The characters can use spells or other resources to mitigate some of the negative consequences but they cannot take a long rest at the end of the fast travel in an attempt to immediately mitigate negative consequences. Additionally, the characters will sometimes arrive and begin the session in a "hot start." This means the session will begin in an encounter whether that be social, exploration, or combat.
Once characters have fast traveled to a location they immediately begin exploring/interacting with that location. For example, if the adventurers fast travel to the Lost Temple Ruins they begin in the Lost Temple Ruins or at an entrance to the Ruins (if the entrance is somehow barred). The adventurers can explore/interact with the location until they complete it or decide they wish to retreat. Completing a location may mean defeating all the enemies at that location, defeating a specific enemy, finding a treasure or NPC and escaping with the same, solving a puzzle, etc. The DM will notify the players when they complete a location and offer the characters an opportunity to take specific actions before ending the adventure. For example, players may wish to search for secret rooms, interact with objects, or speak with certain NPCs.
If the party decides to retreat from the location for any reason, that will conclude the adventuring portion of that session. For example, characters enter the Lost Temple Ruins and after clearing a floor worth of enemies they decide that it is too dangerous to continue onward. Those characters can elect to retreat and that will end the adventuring portion of the session. Depending on the circumstances surrounding the retreat, the DM may call for a skill challenge, encounter, or other sets of obstacles. There is a difference between retreating after clearing out a floor of a dungeon and retreating mid-combat when things are looking grim. It is possible for characters to be captured or killed during a retreat depending on the situation. This is by no means the norm but DMs will apply reasonable consequences based on the situation. Again retreating mid-combat could lead to a skill challenge to flee that combat and a large number of failures could result in severe consequences. Keep in mind this is no more dangerous than staying in the dungeon as dungeons are defined by their danger (risk) and their treasure (reward). Sometimes retreat is the best option.
After a retreat, the session may continue with resolutions of the actions and general roleplay but the adventure will be concluded and no more encounters will occur during that session. In other words, once you retreat there is no more chance of risk but no more opportunity for reward. It is possible this will result in a shorter session. That is understood and ok, failures, setbacks, and low points make achievements, victories, and peaks all the more enjoyable and memorable.