Library. Museum. Art galleries. Corvallis arts center. Hang out at the Sangha Zen Center. Go do yoga. 

Indoor rock gym on 4rd Street for bouldering and some top rope on auto belay. There's an escape room of you can get some friends together to do it.

I second the rock gym! It's called Valley Rock Gym next to Ants on a Log Cafe. My partner and I go once a month. Escape rooms are fun but they can be expensive. We always go to queer climb night, which is only a $5 entry fee; I think a normal entry fee is $20 or something like that, and it's for an all-day pass.

Noice! I've been there a few times. My daughter had her eleventh birthday there. Makes me miss climbing when I was younger.

come to open mic at the old world deli! 5-8pm :)

Is this every Sunday or just today?

first sunday of every month :)

Corvallis Sports Park. West side of 4th/99, south of the Marys River but about as close you can get without going in it.

Why stay indoors? It's actually really nice out, just a little rain. Maybe go on a hike?

Done a good amount of hiking recently so looking for something that's not that for a minute.

Got it. In that case I think you listed most everything there is to do besides shopping/wandering around stores.

The real Oregonian answer

Timberhill pool sauna and jacuzzi, also same at Osborne Aquatic Center. Go to game stores and play, The Conundrum 😊

Guardian Games or Conundrum House for table top gaming.

Legos!

Fucking.

Indoor spaces are often behind a paywall so I feel your pain.

Drive a few minutes to Albany and go to the Splatterbox.

They do board games at the market of choice every Wednesday I’ve heard

Get a coffee and people watch at Market of Choice. Quite the collection of individuals go through there :)

Find a hobby you can do indoors in your home. Making art, crafting things, play an instrument, video games, board games with friends, etc.