Garda Lake is the nearest one to Venice; by train you can travel from Venice Santa Lucia to Desenzano in 1h 50m.

Or you could travel from Venice to Milan (about 2-3 hours) and then take the train an hour north to Lake Como.

we did it the other way we went from Limone on Lake Garda to Venice and it took about 3 hours.

if you read the report returned from venice yesterday i wrote on the 24th april. wife and i enquired at our hotel about visiting lake and the reception told us to go to deszanno (excuse spelling) which was the second train stop at lake which he said was more convenient to get to lakeside ?. we had a walk down a hill for 10/15 minutes to reach the lake/shops etc .allthough shops were shut for a while due to obligatory siesta much to my wifes disappointment.

We did it the other way around - a day trip from Lake Garda to Venice. Travelled by train which took about 2 hours, slightly less on the way back as we got an express train.

Thanks to all of you who have replied to me.

I will certainly try and schedule this in for 1 of our days.

Best Wishes

Too late for this guy, but there's Lake Iseo. Change at Brescia for the train run by FNM to Iseo (for a boat ride to Monte Isola)

http://www.ferrovienord.it/tamtam/pdf/brescia-iseo-edolo2005.pdf