Pea Gravel would not be a preferred walking surface. It reminds me of walking in sand as it rolls under your feet and never compacts well. It is better suited as a drain rock.

Standard 1/4" gravel crushed (angular) was used at depth of 2" on top of a base rock installation of 3/4" crushed rock at a depth of 4". Important to install a non-woven (aka spun bonded) soil separation "landscape fabric" fabric between soil and base rock so that the 3/4" gravel does not get contaminated with soil which can cause settling and drainage problems down the road.

When selecting your gravel surfacing, be careful not to use 1/4" minus or anything with minus if you can avoid it. Minus contains fines which have a way of tracking onto other surfaces where you don't want it, such as your hardwood floors inside. Also if minus is part of the base such as the 3/4" that we used here, it will not drain as well since there will be less void space for water movement and storage.