Haunted bed and breakfast! They actually lock up and leave you (and the ghosts)alone over night! Wonderful old mansion with huge rooms on the top two floors. With dinning on the first floor and in the basement. Which makes for fun creeping around in the dark, late at night!
The best in the country. On Wednesday evenings in the summer they host a free jazz/blues concert. Bring your wine and pinic to enjoy under the stars in the middle of the gardens!
The arch is an interesting experience. Although the ride up to the top of the arch is cramped in small little spaces, the view is breathtaking. The city is gorgeous from that high, but if you look towards the river, you can really see the muck and dirty water from the Mississippi. Downstairs, you can experience the gateway arch museum. It's basically a bunch of historical crap about the midwest. Louis and Clark and the like. Outside, the arch is surrounded by a wonderful park, perfect for picture taking.
There is cheap parking at the arch, along with many different parking garages and such. Also, the roads are easy to navigate if you know where you are going.