Weekend Quick Cryptic 130 - Going Trekking

This time it is my turn to provide the fortnightly Weekend Quick Cryptic crossword, Number 130 in the series. The title "Going Trekking" is a clue to the theme. Can you find all the thematic answers in the completed grid?

You can try and solve the crossword interactively here on MyCrossword or here on crossword.info. As usual you can download a PDF to print which you can find here. Alternatively you can copy and print the image below. Comments and queries are welcome with the solution post (which also gives tips on some of the clues).  I will react to any comments or queries there as soon as I can. You can find an index to the complete series of crosswords here.  

Summer Social. TimesforTheTimes is having a Summer Social at The George, Southwark from midday on Saturday 14th June. All three of your Weekend Quick Cryptic setters are planning to be there. Do come and join us for a drink or two as we celebrate 5 years of the Weekend Quick Cryptic series.

You can find some hints for the perplexed and the solution here and an index to the complete series of crosswords here.