Namida12 has a pretty good take on the ride, coming from someone out of the area.

Always a good idea to have a light wind/rain jacket. Be prepared, be self-sufficient, don't rely on all the helpers and you'll have a better time. When you're training, practice drinking a bottle an hour, eating while riding, etc.

It's really cool to be on the road with so many other riders. Most are pleasant. Some of the groups are not. A mirror on your glasses or helmet is a handy thing.

The route is about the flattest way between Seattle and Portland, not necessarily the most scenic part of the Northwest, but -- about 5 miles in, if it is clear in the early morning, there is a fantastic view of Mt. Rainier across Lake Washington. Further south, more views of it, Mt. St. Helens, and eventually, Mt. Hood. Starting at 4:45 theoretically puts you in front of some faster groups which you might be able to tag onto for a few miles' tow, if they're willing.

The 10 or 15 miles after the first big rest stop - REI - are in my mind the least safe parts. Rather narrow road, has had potholes hidden in shady areas, etc. Keep your eyes open there.

$25 (or so) for a 15-minute massage at the Centralia half-way stop helped me a lot the last two times I rode.

Stop at the top of the Napavine hill for the banana bread (free, but worth much more).

The bridge at Longview is a grind. 150 or so miles into the ride. Make sure your water bottles are firmly seated for the descent, a lot seem to bounce out. No police escort for one-day riders.

Hwy 30 is not terribly exciting, but on the one-day (my experience) not that bad by 5:00 pm or so. When you get to the city of St. Helens, if you're still hungry after the food stop there, look for the Burgerville for the northwest's best chain restaurant burgers.

If the route into Portland goes over the St. John's bridge, it's a real treat as far as views up there.