Happy hour ahoy!

Chicago's various cruise lines ply the waters of Lake Michigan and the Chicago River pretty much year round (until the river freezes over, at least) during the day, evening and even midnight. But when the long nights of summer arrive, an additional option enters the mix: the early evening cocktail cruise.

From white-tablecloth buffet cruises to zero-frill rides with basic tour-boat commentary, there are cruises (all around happy hour) for all tastes and budgets. Zip along the river and hear more architectural information than can fit inside your skull for less than $30. Gather a group of friends and bob along Lake Michigan -- with open bar, yet -- for about $100 per head. Try a wine tasting. Dance to a DJ.

And return to land with most of the evening still ahead of you.

Two of us sailed on a selection of cocktail cruises and evaluated the experience.

Chicago Architecture Foundation Evening Cruise

The basics: Two-hour river cruise, $28-$32.
Available: 5:30 p.m. Thursdays, 5 and 5:30 p.m. Saturdays-Sundays
Departs: Chicago's First Lady dock, south bank of Chicago River, east of Michigan Avenue.
Features: Tour is narrated by a CAF volunteer, providing virtually non-stop commentary on the riverfront architecture.
Refreshments: Cash bar serves beer, wine, cocktails.
Best for: Architecture fans and serious tourists, though even casual tourists will enjoy the low-key vibe.
For tickets: 800-982-2787, First Lady box office or ticketmaster.com/rivercruise.

Mystic Blue Lake-Breeze Dinner Cruise

The basics: Two-hour lake cruise, $74.66-$80.50.
Available: 6:30 p.m. Mondays- Fridays, 6 p.m. Sundays, 5 p.m. Saturdays (twilight cruise).
Departs: Navy Pier, east end.
Features: No narration. Live music on outdoor deck, DJ and dancing inside.
Refreshments: Price includes light buffet dinner; cash bar. Numerous upgrade packages available.
Best for: Large groups get the best deals, but also fun for romantic couples comfortable in an energetic atmosphere.