Reshaping dataset


I have a dataset that has the following variables:
date stock1 stock2 stock3 etc. where the stockprices are recorded for each stock at each date for 300 dates. But what I want is to reshape the data in stata such that I get date and then a variable prices where each stock is below one another. So I get the date and then the corresponding prices for stock 1 in row 1-300 and an extra indicator variable with the stock1 etc. For stock 2 I want the prices in row 301-601 and the indicator variable should be stock2 and ofcourse the date should be 1-300 again.

Does anyone know how to do this?

Thanks a lot,