Games like Summerland
Games like Summerland include Firewatch, What Remains of Edith Finch, The Beginner's Guide, Gone Home, and Quern - Undying Thoughts. We matched them by the tags players give Summerland on Steam (Adventure, Story Rich, Walking Simulator, Atmospheric, and First-Person): closest matches first, and among equally close ones the better-known games.

Firewatch
Shared: Adventure · Story Rich · Atmospheric

What Remains of Edith Finch
Shared: Story Rich · Walking Simulator · Atmospheric

The Beginner's Guide
Shared: Story Rich · Walking Simulator · Atmospheric

Gone Home
Shared: Walking Simulator · Atmospheric · Story Rich

Quern - Undying Thoughts
Shared: Adventure · Atmospheric · Walking Simulator

DEATH STRANDING DIRECTOR'S CUT
Shared: Story Rich · Walking Simulator · Atmospheric

Outer Wilds
Shared: Story Rich · Adventure · Exploration

Amnesia: A Machine For Pigs
Shared: Story Rich · Walking Simulator · Atmospheric

The Talos Principle
Shared: Story Rich · First-Person · Atmospheric

CARIMARA: Beneath the forlorn limbs
Shared: Story Rich · Adventure · Exploration

Riven
Shared: Adventure · Story Rich · First-Person

Syberia: The World Before
Shared: Adventure · Story Rich · Point & Click

The Painscreek Killings
Shared: Story Rich · Exploration · Atmospheric

The Forgotten City
Shared: Adventure · Story Rich · Exploration

The Vanishing of Ethan Carter
Shared: Atmospheric · Walking Simulator · Adventure

The Talos Principle 2
Shared: Story Rich · First-Person · Walking Simulator

Killer Frequency
Shared: Adventure · Walking Simulator · First-Person

Before Your Eyes
Shared: Story Rich · First-Person · Adventure

INFRA
Shared: Atmospheric · Adventure · Walking Simulator

Journey
Shared: Adventure · Atmospheric · Walking Simulator

Layers of Fear (2016)
Shared: Walking Simulator · Atmospheric · Story Rich

Dimhaven - The Lost Source
Shared: Adventure · Walking Simulator · First-Person

Call of the Sea
Shared: Adventure · Story Rich · First-Person

Blue Prince
Shared: Story Rich · Exploration · Adventure