If I had run Expedition to the Barrier Peaks when it reached me in 1980, the first session might have ended in frustration. Barrier Peaks includes lots of empty rooms. Of the 100 or so rooms on the first level, fewer than 20 contain anything of interest. I would have dutifully let the players poke through 80 rooms of “jumbled furniture and rotting goods,” gaining “only bits of rag or odd pieces of junk.” Two hours into that grind, my players would suddenly remember that their moms wanted them home.
In 1980, we ran every dungeon room at the same speed: The pace where players describe their movement and actions in careful detail because if they fail to look under the bed, they might overlook the coins, and if they never mention checking the door, they die in its trap.
Some dungeon masters then and a few now would say that dutifully running level 1 as a room-by-room crawl builds tension. Besides, Barrier Peaks includes wandering monsters to add excitement. Then as now, the pacing of dungeon exploration depends on players. Some enjoy a more methodical pace while others grow impatient for action. But even players who favor careful play will appreciate skipping the slow parts. After the players poke through three or four rooms full of rubbish, dungeon masters can summarize groups of similar rooms by saying they hold nothing of interest.
Even though modern adventures seldom contain sprawls of empty rooms, they often include locations best summarized. For example, Dragon of Icespire peak includes Butterskull Ranch, a 10 location manor occupied by orcs. Once my players defeated the orcs and nothing threatened them, I summarized their characters’ search of the house instead of forcing a room-by-room waste of play time. When players defeat the main threat in a dungeon and erase most of the peril, they lose patience for careful exploration. You can just summarize the loot and discoveries that remain.
Any site that merits numbered locations can mix areas that deserve different paces of play from square-by-square attention to cutting to the next scene.
As you pace the game at such a site, choose between methodical exploration and a summary based on the novelty, peril, and choices ahead of the players. When players first enter a dungeon, they face all three elements. A new dungeon starts with novelty because players know little about the threats and discoveries ahead. Even with all those empty rooms, the crashed spaceship at Barrier Peaks starts with unprecedented novelty. If a dungeon lacks peril, then its just an archaeological site; summarize the discoveries. Dungeons tend to start with key choices over marching order, light, and strategy. Does the party plan to explore carefully or rush ahead to stop the midnight ritual? Will they listen at doors or check for traps? Does someone scout?
Once these choices set a pattern and the dungeon starts to seem familiar, DMs can summarize the exploration until the situation changes.
Especially when you run a big dungeon like Barrier Peaks, you can switch your pace between methodical exploration and summary many times during a session. In the areas with nothing new to discover and no threats to face, take the shortcut of summarizing. Then when the players encounter something new, slow to a pace that lets them account for every action. “What do you want to do?”