visit to cinque terre

Start in Monterosso work your way back. If you are able there is a nice hike from Monterosso to Vernazza. Then, take the little train to the next town and so on as each town is only 5 to 10 minutes apart. Just buy a train ticket from the machines real simple it takes credit cards and you can buy more than one, though there is some kind of 1 day Cinque Terre Train pass you get.
http://www.cinqueterre.eu.com/en/cinque-terre-timetable

I would not plan a set time I would stay until sundown at least as that is when all the day tripping cruise ships etc hoards leave after 6 pm. It is better at dusk with the local housing lighting the towns. Or take the next to last train leaving back to Pisa. Keep the train schedule back to Pisa in mind so you don't miss it but don't rush

"Nice hike" from Monterosso to Vernazza is a bit of an understatement. It is a beautiful hike, but on the strenuous side. We had planned on hiking from Monterosso to the last of the five towns; but after hiking from Monterosso to Vernazza, we took the train from Vernazza to the town after Corniglia - can't remember the name off the top of my head. There are places to refuel in every town - and you will need them.

With that said, we were passed by what seemed like thousands, but were probably just "many" young Scandinavian women who shed their tops and hiked past us in their bras, not to my husband's annoyance.

Yeah, the Cinque Terre is very busy and crowded especially in season. FYI, you'll need to buy a hiking pass anyway to hike between towns - and you can just buy one ("CINQUE TERRE CARD TRAIN (Treno)") that includes the hiking pass and regional trains all day, too, between Levanto and La Spezia (includes the five villages). Probably worth it if you will take more than one train in the area. And you can buy your ticket back to Pisa leaving from La Spezia at the end - might save you a few bucks.

http://www.cinqueterre.eu.com/en/cinque-terre-card

This is the website for the Cinque Terre National Park and the page you need for info on the train card:

http://www.parconazionale5terre.it/page.php?id=158

This will allow you to "hop on/hop off" the trains as long as it's for 2nd class seats on regionale or select regionale fast trains. I would say 6 hours isn't enough to try and squeeze in a day exploring the region. Depending on time of year and amount of daylight, I'd push it to as long a day as you can manage. The train station for the village of Corniglia is far below the actual village itself so you'll need to climb a long switchback stairway up to the town or catch a ride on the little buses which are roughly timed to meet incoming trains. A Cinque Terre Treno MS Card (linked above) will cover the cost of that ride both directions.

You only have to validate the pass the first time you use it.

smitty,

This is my suggestion for visiting the five towns.....

• start in Riomaggiore (the southern most town), which the train from Pisa will likely go through first anyway. From the rail station, you'll have to walk through the pedestrian tunnel (which parallels the tracks) to reach the main part of town.
• take the train to Manarola. You might want to take the path behind the station up to the small bar at the start of the famous Via dell' Amore and have a glass of Vino or a snack, while enjoying the awesome views.
• take the train to Corniglia. As others have said, you'll need to use the small shuttle van to get from the station up to the town, unless you're energetic and don't mind hiking up hundreds of stairs.
• take the train or hike to Vernazza. If you decide to hike, you'll need to have a Park Pass. That segment of Sentiero Azzurro trail is not quite as challenging as the segment from Vernazza to Monterosso.
• take the train to Monterosso. Allow more time here since the town has two parts, an "old town" and a "new town" and also a nice beach. There are lots of nice restaurants, so it would be a great place to have an early supper. Cantina di Miky is a big favourite with many here (it's close to the station). Be sure to check the train return time to Pisa, so that you don't "linger" too long over supper.

The Cinque Terre is not far from Pisa so it would certainly be feasible to plan a 10 hour day there. If you leave Pisa right after breakfast and return in the evening, that will allow adequate time to look around the five towns.

There's also a boat that travels between all the towns (except Corniglia) but I didn't suggest that as it takes longer and it's not an efficient use of time with such a short trip. The train trips between towns are only about 10 minutes each.

The train you'll be taking between Pisa and the Cinque Terre will likely be a Regionale. It's very important to validate (time & date stamp) tickets prior to boarding the train on the day of travel, or you'll risk hefty fines which will be collected on the spot.