Helsinki

Depends on what you wanted to see. 5 days is a long time for Helsinki, so you might get an itch to leave the city to see something else. My impression of the area surrounding Helsinki (just beyond the rather drab-appearing suburbs) was that it's pretty sparsely populated, and most of the settlements and infrastructure seems to date from the past 50 years or so. Although I wouldn't recommend it on a shorter trip, with 5 days you may as well have a look at nearby Porvoo. It has a preserved historical section that's worth a quick visit. It probably won't leave you breathless (particularly in April, when I doubt the heritage railroad operates), but it might provide an interesting contrast to Helsinki. I haven't visited, but perhaps Turku might be worthwhile. Although it's Finland's oldest city, from what I understand, almost nothing except a castle remains from before the late 19th century. Finland has some great national parks and wilderness areas, but April is likely too early to enjoy them.

I assume the later part of your trip will include Tallinn, Estonia. If not, then a daytrip there is an absolute must. Or better would be an overnight. The recommendations for Porvoo and Turku are excellent, though I have not been myself. I also concur that 5 days in Helsinki is a bit much, especially in April.

Thanks--I knew it wasn't a great time of year that is why I was hoping to find a tour company that did short tours to the north. We may rent a car for a couple of days and go to the area you mentioned.We will make the most out of our time.