CT Topo Map Book

Quite a few CTers have used them. A buddy of mine used it on his CT hike.

They are great for the designated CT corridor. But they are basically strip maps.

If you want to hike alt routes or do some 14ers, they may be limited.

Some map and other resources you can also use:
Colorado Trail Maps and Guuides

I found it useful, both for planning and during the hike.

And +1 for the other resources Mags mentions.

You will not get lost on the CT. But if you do go for alternates I think other map sources might come in handy.

At any given intersection people have nailed up half a dozen markers in each direction.

And I highly recommend doing any alternate route from Twin Lakes -> Monarch Pass. CT through this stretch is–well–lame. I'd recommend the CDT. You go over 3 or 4 awesome passes while the CT skirts the front of the Collegiate Peaks. However, much of that route is 4×4/ATV/dirt bike shared trail. If you hit it during the middle of the week you probably won't see, hear, or smell much of them.

@Matt: What segments are you talking about? Can't look at the book right now. I have a timeline made already so I'd be able to tell what day I'd hit that alternate route.

Twin lakes is in segment 11, immediately after Elbert. And Monarch Pass is at US-50, the division between segments 14 and 15–this is where you'd get off to go to Salida. Hitching from the CDT crossing at Monarch pass is infinitely easier than the CT crossing which is a few miles down the road. Monarch pass has some tourist trap/restaurant compared to the CT which is a shoulder pull off. Not that Salida is that easy to get to–took me at least 2 hitches the 4 times I went in and out–but 'Hey, mister…" always works better than standing on a shoulder.

edit: If you're not a purist I'd also not follow the CT/CDT around twin lakes–scenic but unnecessarily long since you're basically following the road. If you take the Twin Lakes trail into town (I assume you're starting in Denver) or just hike into the town from the trail/road crossing and follow the road out of town probably .1 mile and go left on an old gated jeep road (I'm pretty confident its the only thing on the left out of town). Follow this and ford the lake's tributary–the jeep road crossing on the other side is slightly up stream and you can follow this to the Hope Pass trail/CDT. Short cuts the lake and avoids hiking an extra couple miles to cross the river upstream at a pump house. Smarter not harder…

One place to watch out for is the trail into Breckenridge. There were lots of down trees there that might have taken out trail markers. A lot of intersections were unmarked and the official guidebook and Eric the Black's Guide that my friend carried were inadequate.

As a side not Eric the Blacks guide looked better than the official version to me with one small problem. Eric is more optimistic about water sources. He might mark a water source as reliable while the official book marks it as seasonal (and thus something you don't want to rely on if its dry). I get both mark the questionalbe water sources down in Eric's book and take it.

The topo book is great for planning your trip, but is not to be relied on completely as it doesn't contain the re-routes and workarounds for each year. Of course you should (days before starting) check the CT web site for current updates. Another good resource is using the GPS waypoint downloads (purchased from the website as well) and printing your own maps for the areas that are either in question or alternate routes, 14ers, etc.