eBay Seller mkphilanumsis offering an interesting item: India ’80 Gandhi Dandi March Route FD Cncl Set of 7 FDC 

India 02 – 10 – 1980 Dandi March 7 first day covers bearing first day cancellations from 7 different cities, which were on the route to Dandi. Gandhiji stopped at these cities and addressed public meetings in 1930 on the way to Dandi for Salt Satyagraha. The cities are as under:

1) Gandhi Ashram (Sabarmati Ashram), Ahmedabad – The starting point of the Dandi March,
Gandhiji left the Ashram on 12th March 1930

2) Nadiad

3) Anand

4) Bharuch (Broach)

5) Surat

6) Navsari

7) Dandi – The final destination of the Dandi March. Gandhiji Reached Dandi on 5th April and
broke the Salt Law by picking a lump of salt on 6th April 1930.

A real hard to find set of place cancellations, very much useful for any Gandhi collection.

India '80 Gandhi Dandi March First Day Cover wi Dandi Cancellation