Built-in Above Head Shelving

[SVOboy]

Hi all,

Wish I'd taken a picture, but I'm stupid.

In my new house here in Japan they are rather low door trims (about 5'8") and above that around the edge of my bedroom I'd like to put in some book/junk shelving. Should be strong enough to hold books and not look terrible.

I haven't much experience with woodworking (at least not in my adult life). Think I can accomplish this fairly easily? I worry the the length of the shelf along the room and the lack of bottom support might make it complicated. Thoughts?

Thanks!