About Boltline

Boltline is a collaborative guidebook for climbers.

It's a project of Marcacci Labs, Inc. and is currently in an "alpha" state. We're working extremely hard on this and would love to hear from you if you have questions or ideas!

Message us on Instagram, Facebook, or Twitter, or send an email to mike@boltline.org.

Affiliate Relationships

Boltline has partnered with several online merchants who offer the products we love.


You already know these guys. Whenever a climb or area references a book with an ISBN, we generate a link to the book in Amazon. When traveling to a new climbing area, the local gear shop is often the best place to pick up the book: it's likely staffed with experienced local climbers who can answer questions and give you personal recommendations. However, when it comes to buying books online, it's hard to beat Amazon.

Nodal Ninja

Nodal Ninja creates world-class panoramic heads, which are used to create super-resolution photos. These make exceptional base photos for zoomable topos, showing both detail and context. To save 10% off any of their products, reach out to us and ask for a link and coupon code!